Digital Commons Network^™

The United States National Security And Policy Implications Of Desertification, Eric Olvera

Open Access Theses & Dissertations

Contemporary climate security literature reveals that desertification appears to be overlooked as a climate change security threat to the United States (US). This investigation demonstrates that an inequity exists between sea-level-rise- and desertification-based climate security literature. This inequity may reveal that the US may be ignoring desertification at a time when land use in some dryland areas is reaching a critical point where it can no longer support human activity. Due to the interdisciplinary nature (science and security) of this work, a review of the terminology used in the article is provided to establish a baseline understanding of “desertification” and …

Assessing Sedimentation Impact Through Dem, Point Cloud, And Discharge Analysis, Shandell Thomas

Open Access Theses & Dissertations

This study focused on five arroyos flowing into the Rio Grande, in the stretch between Caballo Dam and Las Cruces, New Mexico. Drone imagery was acquired from study areas in each arroyo. Photogrammetry was used to create high-resolution digital elevation models (DEMs), point clouds, drone imagery and potential discharges were acquired for each arroyo. Investigation of seven different methods resulted in the selection of the Terrain Ruggedness Map (TRM) as a predictor of surface roughness, along with high-resolution DEMâ??s to illustrate small and low-relief channel features. The five arroyos with varying sediment sizes and characteristics were studied to understand how …

Rockets, Rovers, And Rocks, Oh My!, Tara Lynn Sweeney

Open Access Theses & Dissertations

This body of work undertakes three distinct projects, all with the ultimate goal of improving the future efforts of human space exploration.Chapter 2 is a seismic analysis of rocket launch and landing operations. Being able to identify and understand anthropogenically induced seismic signals in comparison to naturally occurring seismic signals is an important step in characterizing and monitoring both types of signals on the Moon. Relatively few terrestrial studies have been performed to explore this, but there is a growing opportunity to record, discern, and understand the differences between anthropogenic and naturally occurring seismic signals due to the increasing pace …

Heavy Metals In Rural Soils: A Case Study In Jennings County, Indiana, Madeline Hill

All-Inclusive List of Electronic Theses and Dissertations

Heavy metals, such as lead and mercury, can be toxic if exposure levels are too high. People are often concerned about lead exposure from water or paint, but soil is another potential exposure avenue for many metals. While some heavy metals, including mercury and lead, are found in emissions from coal-burning power plants and from incinerators, many metals accumulate in soils from past uses (ex. lead paint, leaded gasoline, chemical spills, industrial emissions, and natural occurrences). It is important to have soil tested to check metal concentrations because consumption or inhalation of these metals can lead to permanent damage and …

Geochemical Evidence Of Drying During The 4.2 Ka Event In Sediment Cores From The Yucatán Peninsula, Mexico, Derek K. Gibson, Jonathan Obrist-Farner, Alex Correa-Metrio, Alejandra Rodriguez-Abaunza, Carlos Castañeda-Posadas

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Tropical hydroclimate variability during the Middle and Late Holocene was investigated using geochemical indicators of local-scale precipitation and evaporation preserved in sediment cores from two sites in the Mexican Yucatán Peninsula. Scanning X-Ray fluorescence spectroscopy data show generally decreasing precipitation trends during the Early and Middle Holocene. During the transition between the Middle and Late Holocene, geochemical evidence of reduced watershed erosion and increased evaporation indicate that a centennial-scale drying event impacted the region between 4.3 and 4.0 ka (kilo-anum; thousand years before present). These findings suggest that the 4.2 ka drying event, which has been previously recorded in Europe, …

Experimental Evaluation Of A Recrosslinkable Co2-Resistant Micro-Sized Preformed Particle Gel For Co2 Sweep Efficiency Improvement In Reservoirs With Super-K Channels, Adel Alotibi, Tao Song, Ali Al Brahim, Baojun Bai, Thomas P. Schuman

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A recross linkable CO₂-resistant branched preformed particle gel (CO₂-BRPPG) was developed for controlling CO₂ injection conformance, particularly in reservoirs with super-permeable channels. Previous work focused on a millimeter-sized CO₂-BRPPG in open fractures, but its performance in high-permeability channels with pore throat networks remained unexplored. This study used a sand pack model to evaluate a micro-sized CO₂-BRPPG under varying conditions of salinity, gel concentration, and pH. at ambient conditions, the equilibrium swelling ratio (ESR) of the gel reached 76 times its original size. This ratio decreased with increasing salinity but remained stable …

The Palaeoclimate Potential Of Continental Scientific Drilling, Jonathan Obrist-Farner, Lesleigh Anderson, Paul Baker, Melissa A. Berke, Emily J. Beverly, Julie Brigham-Grette, Erik Brown, Isla S. Castañeda, Alan L. Deino, Sherilyn C. Fritz, Steven L. Goldstein, Natalie M. Kehrwald, Matthew Kirby, Kenneth G. Miller

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

No abstract provided.

Landslide Inventory And Unstable Slope Monitoring Along Highways In Eastern Tennessee, Robert Mcsweeney

Electronic Theses and Dissertations

This research introduces an unstable slope management program (USMP) for Tennessee based on federal slope management standards, along with improved methods for landslide monitoring with unmanned aerial systems (UAS) lidar and photogrammetry. In mountainous regions, monitoring slope hazards is a critical function of transportation management. A mobile field assessment form created with Survey123 was used to collect 22 unstable slope ratings in eastern Tennessee. Location points were appended with photographs, notes, and site information. Landslide scores ranged from 325 (Fair) to 1005 (Poor). UAS monitoring of a slow-moving soil landslide along I-40 near Rockwood, TN, produced high-resolution lidar and photogrammetry …

New Constraints On The Stratigraphic Architecture And Evolution Of Mississippi River Delta Lobe Activity: Barataria Basin, Southeastern La, Wilke Coleman

LSU New Orleans Theses and Dissertations

Barataria Basin is a shallow water, interdistributary estuary that has evolved in response to dynamic depositional regimes governed by distributary avulsion and reworking of sediments by coastal processes. In the Mississippi River delta plain, the migratory nature of the River has produced an evolving landscape constructed through episodes of regressive and transgressive sedimentation. These processes produce unique depositional signatures in the stratigraphic record, however the transgressive component of the delta cycle often results in obliteration of the regressive phase. This study uses a modern suite of geophysical and sediment core data to construct a revised geologic framework in Barataria Basin, …

Testing For Patterns Of Deformation From The Yellowstone Hotspot Along The Gallatin River, Sw Montana, Jack Willard

All Graduate Theses and Dissertations, Fall 2023 to Present

Yellowstone has fascinated humans for thousands of years. Geologists have addressed many of the region’s mysteries, including the underlying mantle hotspot, the chain of calderas tracking the motion of the North American Plate over this hotspot, and the risks posed by the super volcano. However, the way that the hotspot impacts regional tectonics and topography remains under-studied. Influential previous work recognized the Yellowstone Crescent of High Terrain (YCHT), an arc of high topography around the Yellowstone Plateau with limbs extending to the west and south into central Idaho and northern Utah. The YCHT is also hypothesized to be the pattern …

Using Luminescence Dating To Investigate Geomorphic And Archaeologic Features At The Wiggins Fork Bison Jump Complex, Northwestern Wyoming, Emma T. Krolczyk

All Graduate Theses and Dissertations, Fall 2023 to Present

The Wiggins Fork Bison Jump Complex, located in northwestern Wyoming, is comprised of thousands of human-placed rock piles, known as cairns, that were placed within lines to form an extensive network of drivelines and funnels leading to cliffs or steep slopes. These archaeological features were used by Native Americans as a bison hunting method, where the animals were driven off cliffs for harvest. This research uses luminescence dating, which determines when sediment was last exposed to sunlight, to date the timing of driveline construction and the deposition ages of the underlying river deposits.

Research focused on Jump #4, which had …

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

Publications and Research

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

A Python Pipeline For Rapid Inversion Of Gravity Data Aimed At Early Career Researchers: Application To The Lost River Fault, Idaho, Bradford C. Mack

USF Tampa Graduate Theses and Dissertations

Gravity data and modeling can be used to create a 3D view of basin and fault geometries, a valuable tool for seismic hazard assessment. Additionally, access to a high-speed, easy-to-use modeling workflow will enable more researchers to supplement their work with a new method and allow students to be exposed to modeling earlier in their academic careers. The primary goals of this work are to create a widely usable 3D gravity and basin model, to create an introduction to modeling teaching module for undergraduate geology students, and to apply the model to the northernmost two segments of the Lost River …

Statistical Methods For Interpreting Spatial And Temporal Heterogeneity Of Martian Tropical Water Ice Informed By Properties Of Crater Ejecta Types, Jamie D. Riggs, Michelle R. Kirchoff

College of Population Health Faculty Papers

The martian tropical water ice spatial and temporal distribution was characterized using impact crater ejecta type, location, size, and age in one of two epochs, (Formula presented.) Ga and (Formula presented.) Ga, using statistical models designed for spatial and temporal correlation structures. The indicator thought to identify the presence of ice is craters with layered ejecta, while the indicator thought to identify no ice is craters with radial ejecta. These indicators imply the location (longitude and latitude) and, potentially, depth (crater diameter as a proxy) of ice, and when the ice was present. The spatial and temporal distribution of layered …

Construction, Emplacement, And Structure Of Cretaceous Plutons In The Ebbetts Pass Region, North-Central Sierra Nevada Batholith, California, Hollianne C. Mcclure

Master's Theses

Field, petrographic, and geochronologic analyses were conducted for five Cretaceous plutons in the North-Central Sierra Nevada batholith to better understand their construction, emplacement, and deformation histories. All the plutons in the study area were constructed incrementally, but timing and degrees of mixing between increments vary. The lack of internal contacts and heterogeneity in the interiors of the Stanislaus Meadow and Ebbetts Pass plutons suggest that there were sizeable magma chambers where there was thorough mixing of increments. The West of Elbow, Lookout Peak, and Kinney Lakes plutons were constructed from small batches of magma based on their textural and compositional …

Active Tectonics, Erosion Rates, And Topographic Metrics In The Hayword-Calaveras Fault Zone, Simone I. Yeager

Master's Theses

In northern California, the complex geometry of the San Andreas Fault system, and how it steps and propagates across the Earth’s surface, is revealed in the topography. Activity along the Mission and Arroyo Aguague oblique reverse faults, located where the right-lateral Hayward Fault steps to the left of the Calaveras Fault, are manifested in the Diablo Mountain Range. The high topography in the restraining step can be observed in lidar imagery and seismicity studies show these faults are connected at depth. In this study, we investigate active tectonics, erosion rates, and topographic metrics from the southern end of the restraining …

No Change In Functional Ecology Or Body Size In Response To A Global Climate Event In The Late Maastrichtian Owl Creek Formation, William T. Rizza

Master's Theses

During the last 300 ka of the Maastrichtian, global temperatures increased and decreased by ~2℃, likely caused by a pulse of Deccan volcanism. The Owl Creek Type Section in Mississippi records some portion of the last 400 ka of the Late Maastrichtian. It is expected that marine invertebrates will demonstrate a taxonomic, ecological, or morphological response to rapid temperature change. I anticipate a decrease in taxonomic diversity and shell volume and an increased abundance of low activity-level species, similar to the ecological impacts observed in response to Large Igneous Province eruptions in the geologic record. Clumped isotope paleotemperature reconstruction recovers …

Assessing Climate Change-Induced Drought In Abu Dhabi, Salem Anwar Alblooshi

Thesis/ Dissertation Defenses

This thesis examines trends of drought related to climate change in a region within the Abu Dhabi Emirate through advanced remote sensing and statistical trend analysis techniques. To analyze long-term trends in temperature, precipitation, evapotranspiration, and groundwater levels, we use Google Earth Engine (GEE) as our primary data extraction and analysis tool, covering the years from 2002 to 2016. Evaluation of MODIS Land Surface Temperature data indicated a statistically significant warming trend each month, with rates reaching as high as 0.1°C/year. Although precipitation patterns revealed significant variability without any major trends, evapotranspiration values showed a predictable increase, especially during the …

Using Convolutional Neural Network To Determine Time Window For Analyzing Local Shear-Wave Splitting Measurements, Yanwei Zhang, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The time window for analyzing local shear-wave splitting (SWS) phases significantly affects the quality of measurements, revealing a noteworthy domain influence. In this study, an approach using convolutional neural network (CNN) is applied to determine the end of time window (e), which has a similar idea of the phase-picking CNNs. The start of time window is 0.5 s before e. Our data set contains 803 human-labeled measurements, recorded from three stations located in Ridgecrest, California. These measurements are foreshocks and aftershocks of an M 7.1 earthquake on 6 July 2019. After 21 times shifting on each measurement, 90% of the …

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

Student Summer Scholars Manuscripts

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

Accumulation Of Road Salt In A Calcareous Fen: Kampoosa Bog, Western Massachusetts, Wayne Ndlovu, Andrew J. Guswa, Amy L. Rhodes

Geosciences: Faculty Publications

Road salt poses a threat to the quality of soils and water resources. Wetlands located in salt contaminated areas are at risk of experiencing lower plant and animal species diversity. Therefore, it is critical to understand how modifications to salt application rates and hydrological events impact wetland water quality. Here, we use chloride mass flux, discharge, groundwater chloride concentration, meteorological, and salt application data from 2012– 2020 to estimate chloride accumulation and outflux rates in the Kampoosa Bog subwatersheds, located in Stockbridge and Lee, Massachusetts, and bordered by major highways (Interstate-90 and U.S. Route 7). We also investigate the correlation …

Effects Of Longitudinal Training Walls On Two-Dimensional Flow Structure, Sediment Transport, And Bed Aggredation Using Numerical Methods And Sediment Core Analyses In Grand River, Michigan, Sumaiya Tul Siddique

LSU Doctoral Dissertations

Longitudinal training walls (LTWs) are structures oriented parallelly with the main flow and separate the channel into two sub-channels. One channel acts as the main navigational channel and the other is considered a secondary side channel. The long-term effects of the LTWs on morphodynamics and deposition remain poorly understood. This study investigated the long-term effects of the LTWs on flow, sediment transport and long-term deposition of the Grand River using numerical approaches and sediment core analysis. The effects of LTWs on 2D flow dynamics and sediment transport were investigated by using numerical approaches. The long-term deposition under the influence of …

Revealing Grounding Zone And Subglacial Processes At Cosgrove Ice Shelf: Seafloor Analogs For The Modern Antarctic Ice Sheet, Rosemary E. Burkhalter-Castro

USF Tampa Graduate Theses and Dissertations

The future loss of ice in West Antarctica is one of the biggest uncertainties in projections of global sea level rise. The West Antarctic Ice Sheet (WAIS), home to Cosgrove Ice Shelf (CIS), contains enough ice to raise global sea level by more than three meters if it collapsed completely. Accurately predicting how much sea level change may occur from a future collapse of WAIS is of particular interest to low-lying, heavily populated coastal areas such as Florida. For this reason, it is important to understand the processes underpinning rapid changes and retreat at marine-terminating glaciers in the Amundsen Sea. …

Modern Lakeshore Processes And Historic Lake And Glacial Changes In Taylor Valley, Antarctica, Michael Stanley Stone

LSU Doctoral Dissertations

Taylor Valley, which opens to the Ross Sea, is one of several ice-free valleys comprising the McMurdo Dry Valleys, Antarctica. The valley is home to several close-basin, perennially ice-covered lakes, whose lake levels largely reflect a balance between meltwater inputs and lake ice ablation; both being driven by climate. A dynamic environment exists where the lake ice covers meet the lakeshore, with the ice grounding to the substrate throughout the cold and dark of winter, and melting to form a perimeter of thin-to-no ice around the lake during the summer. These marginal freeze-thaw regions are known as moats. Here, physical, …

Re-Evaluating Hypertragulid Diversity In The John Day Basin, Oregon, Usa, Nicholas A. Famoso, Lana K. Jewell

Geology Faculty Publications and Presentations

Despite their relative abundance, members of the family Hypertragulidae (Artiodactyla, Mammalia) have proved a conundrum regarding species diversity in the Turtle Cove Member (Oligocene) of the John Day Formation, located in central and eastern Oregon. Three species and two separate genera are described in the area, but previous research lacks statistical support for this level of variation. We use coefficients of variation (V) on measurements of dentition and astragali of hypertragulid specimens designated Hypertragulus hesperius, Hypertragulus minutus, and Nanotragulus planiceps as a metric for determining whether there were multiple species present in the population. Asymptotic and modified signed-likelihood ratio V …

Projected Loss Of Rock Glacier Habitat In The Contiguous Western United States With Warming, Abigail C. Lute, John T. Abatzoglou, Andrew G. Fountain, Timothy C. Bartholomaus

Geology Faculty Publications and Presentations

Rock glaciers support alpine biodiversity and may respond more slowly to warming than snow or glaciers. While responses of snow and glaciers to climate change are relatively well understood, a robust assessment of rock glacier environmental niche, future distributions of rock glaciers and potential for development of rock glaciers from current glaciers is lacking. Using process-relevant, high-resolution environmental descriptors, we develop a species distribution model of the topographic, geologic and hydroclimatic niche of rock glaciers that provides novel estimates of potential rock glacier distributions for different climates. We identify mean annual air temperature and headwall area as the dominant controls …

Kentucky Geological Survey Landslide Inventory [2024], Matthew M. Crawford, Evelyn M. Bibbins, Hudson J. Koch

Research Data--KGS

The KGS landslide inventory provides the locations of known landslides and areas susceptible to debris flows. Various types of landslides are represented including slides, flows, rockfalls, and creep. The data are available as ArcGIS geodatabase feature classes. Landslide locations and associated attributes are compiled from Kentucky Geological Survey research, published maps, state and local government agencies, the public, and media reports. A confidence ranking system assigns a value to each feature. A description of the feature classes is here: https://kgs.uky.edu/kgsmap/helpfiles/landslide_help.shtm

The inventory viewed in a GIS with geology, soils, slope or other terrain-based data can serve as a basis for …

Engaging Students In The Scientific Process: An Examination Of Active Learning Strategies In Introductory Geoscience Labs, Meryssa Piper

Theses and Dissertations

High-quality instruction of introductory geoscience courses entices students to major in geoscience fields and ensures undergraduate students have opportunities to learn and apply scientific information and practices. Prior studies indicate that active learning strategies in higher education settings can increase student knowledge and interest. This dissertation explores the integration of two active learning strategies in introductory geoscience laboratory courses: inquiry and gamification The first study housed in Chapter 2 investigates the level of inquiry used in introductory geoscience lab activities across the United States. Through a comprehensive analysis of these activities, this chapter assesses: (1) the degree to which instructor …

The Fifth Element In Three Dimensions: Boron Systematics Along And Across The Aleutian Volcanic Arc, Owen Jensen

Theses and Dissertations

This study uses abundances and isotope ratios of the fluid-mobile element boron (B) to better understand the role of fluids in volcanism at the Aleutian arc in Alaska. In volcanic rocks from the Aleutian volcanic front, patterns in B abundance and isotope ratios (δ11B) point to three endmembers: a sediment melt, a slab interior melt, and a slab-top melt. Most lavas from the eastern Aleutian Islands have δ11B of -2 to +5‰, similar to Aleutian sediment. Hence, sediment is likely to be the dominant B source in the Aleutian Island samples. In lavas from the western Aleutian seafloor, high δ11B …

A Community-Level Investigation Of Heavy Metal Pollution In Street Sediments From Terre Haute, Indiana, Kyra Copp '25, Kenneth Brown, Nora Bedwell '26, Camden Brown '25

Annual Student Research Poster Session

Urban environments contain environmental legacy issues that can have long-term negative public health consequences. Investigating these legacy issues can help constrain potential sources and their impact on communities. This study focuses on street sediment found in Terre Haute, Indiana, a city with an extensive history of coal-fired power production, high-traffic volumes, steel manufacturing, and Pb-based paint usage. This research specifically focuses on Terre Haute’s Sheridan Park community. Six bulk street sediment samples were analyzed by pXRF at DePauw University. This analysis revealed elevated concentrations of Pb (22-152 ppm), As (8-15 ppm), Cu (35-237 ppm), and Zn (149-634 ppm) in all …