Geology Commons^™

The Role Of Heterogeneity In Earthquake Rupture Dynamics: Insights From Friction Experiments On A 1-Meter Laboratory Fault, Alejandro Aguilar

All Graduate Theses and Dissertations, Fall 2023 to Present

Tectonic faults are made of many kinds of rocks and minerals, creating natural weak and strong zones along faults where earthquakes occur. These differences can affect how faults move, including whether slip occurs slowly and quietly or suddenly and destructively during an earthquake. However, it is not fully understood how these variations influence when earthquakes start, how fast they spread, and whether they stop or grow into large ruptures. This research studies how different fault materials interact during earthquake slip. Using a large laboratory machine that simulates fault movement under realistic conditions, we recreate earthquake processes and closely measure how …

Mining Legacy And Wildfires: Interfacial Reactions Affecting Metal Mobility, Eresay Alcantar-Velasquez

Earth and Planetary Sciences ETDs

We identified water labile interfacial reactions between laboratory burned pinewood ash and mine waste solids that influence metal mobilization. The Upper Gallinas Creek Watershed in New Mexico is affected by wildfires and mining legacy. Pinewood and mine waste sediments were sampled from the area, and the pinewood was burned at 350°C to simulate medium burn intensity ignition. Rapid desorption and gradual dissolution of Mn and Fe was detected by ICP-MS as pH decreased over time. After reacting 18 MΩ ultra-pure water with a mixture of pinewood ash and mine waste sediments Fe (143%) and Mn (89.2%) concentrations increased over time. …

Mapping Along-Strike Changes In Shallow Subduction Zone Geometry At The Alaska Subduction Zone Using Seismic Reflection And Tectono-Geomorphic Analysis, Madelyn K. Hurd

Earth and Planetary Sciences ETDs

The Alaska subduction zone, where the oceanic Pacific plate subducts beneath the continental North American plate at a rate of 60-66 mm/yr, has hosted more >M8 earthquakes over the last century than any other subduction zone globally. The largest of these, the 1964 M9.2 Alaska earthquake, ruptured 800 km of the margin, including a high slip patch near the trench offshore Kodiak Island. The 1964 rupture area may have overlapped with the 1938 M8.3 Semidi earthquake rupture zone that lies to the west. Slip propagation near the subduction trench during large earthquakes can control tsunamigenesis, and differences in wedge geometry …

Reading The Martian Surface: Impact Crater Distributions And Geochemical Signatures In Gale Crater As Recorded By The Curiosity Rover, Megan E. Hoffman

Earth and Planetary Sciences ETDs

The Curiosity rover has been exploring Gale crater, a large impact basin near the Mars equator since 2012. This mission has greatly improved our ability to explore the surface of Mars with a suite of geologic tools and cameras and has revealed that Mars likely once resembled present-day Earth. In this dissertation, I utilize measurements and data taken by Curiosity to analyze the distribution and preservation of small impact craters at meter scales, I quantify the formation characteristics of a small impact crater cluster, and I examine the presence of barium in a geologic unit with high-Si to constrain sediment …

Hydrus Modeling Of A Sahelian Agroforestry System: An Investigation Of Local Water Balance, Nicole A. Butler

Master's Theses

Effects of drought can devastate agricultural productivity in the West African Sahel. Climate complexities, such as lower-than-average rainfall and high winds, can lead to crop failure and low yields, thereby creating food security issues. Agriculture in the Sahel is primarily rainfed, and the rain is becoming increasingly unpredictable due to the changing climate. The method of intercropping groundnut (Arachis hypogea) and pearl millet (Pennisetum glaucum) with the shrub species Piliostigma reticulatum can combat the effects of climate change and restore degraded soil. Intercropping can increase water availability and crop yield when compared to crops grown in the absence of shrubs. …

Exploring Paleoproterozoic Marine Redox States In A Young Banded Iron Formation From The Needle Mountains, Jaya Sharma

Earth Sciences Undergraduate Senior Theses

Banded iron formations (BIF) are redox-dependent chemical sedimentary rocks that have served as proxies for marine and atmospheric oxygen and iron conditions throughout Earth's history. While abundant in the Archean and early Proterozoic, the widespread deposition of BIFs declined following the Great Oxidation Event, as oxygenated surface waters prevented the accumulation of ferrous iron. However, the Needle Mountains, located in southwestern Colorado, house an anomalously young BIF deposited between 1786±10 Ma - 1801±6 Ma given existing geochronology. Here, we use rare earth element (REE) systematics, bulk chemistry, and petrographic analysis to determine the depositional conditions under which this BIF was …

Assessing Spatial Distribution Of Plausible Earthquake-Triggered Landslides Relative To Ca. 1000 Ybp Earthquake On The Gales Creek Fault, Jacqueline Rheingans

University Honors Theses

Modern coseismic landslides cluster near the surface trace of the fault that ruptured, suggesting that clustering of paleolandslides may record information about paleoearthquakes. This study documents the pattern of prehistoric landslides near the Gales Creek Fault (GCF), northwest Oregon, to assess whether it reflects an independently known paleoearthquake. The GCF is located northwest of Portland through the Cascadia fore-arc basin where landslides are often triggered by intense rainfall during the wet season or potentially by seismic shaking on the megathrust or on crustal faults. In order to understand how a seismic event on the GCF will impact landslide distribution I …

The Case For Ice Rises At Ross Bank Since The Middle Miocene, William Weber

LSU Master's Theses

Many tens of ice rises exist at the marine margins of the Antarctic Ice Sheet. Isle-type ice rises in particular are those where an ice shelf is pinned to an underlying submarine bank. Recent and ongoing studies show that Ross Bank, on the middle continental shelf of central Ross Sea, was the former site of an important Ross Ice Shelf ice rise during the advance and retreat of the West Antarctic Ice Sheet (WAIS) in the last glacial cycle. Ross Bank is a broad and anomalously shallow water platform whose crest rises to 170 m water depth. Despite their importance …

Investigating The Distribution And Origin Of Pitted Mounds On Mars Using Machine Learning-Based Mapping And Integrated Geological Analysis: Application To Isidis Planitia, Precious Batubo

Doctoral Dissertations

Pitted mounds are widespread landforms across the northern plains of Mars, yet their origin remains uncertain. These features have been interpreted as possible expressions of subsurface fluid activity, including sedimentary volcanism, magmatic processes, or other fluid-assisted mechanisms. Determining their distribution, morphology, and geology is therefore important for understanding the evolution of subsurface hydrological processes and the planet’s potential for habitability. However, the large spatial extent of mound-bearing terrains makes comprehensive manual mapping impractical. This dissertation presents an automated approach to mound detection using Faster Region-Based Convolutional Neural Network (Faster R-CNN) from high-resolution Context Camera (CTX) images including morphometric and mineralogical …

Hillslope Aspect And Other Potential Controlling Factors On The Spacing Of Periglacial Stone Stripes In Se Oregon, Blue Hansen

University Honors Theses

Stone stripes are a type of patterned landscape that can be polygenetic in origin, but in the High Lava Plains province are interpreted to be relict periglacial features based on similarities to active stone stripe formation in current periglacial settings. Periglacial stone stripes are hypothesized to form via frost process, including ice-driven cracking and soil heave which is dependent on temperature, long-term differences in temperature may contribute to differences in stone stripe patterns or density. Stone stripes in Oregon and Idaho have previously been studied using field techniques, but there is room for reexamination of temperature controls on hillslope density …

Shallow-Marine Crinoid Genera May Have Been More Resilient Across Permian Extinction Events In Terms Of Richness Than Deep-Marine Crinoid Genera, Amelia C. Kolstad

University Honors Theses

Throughout the Phanerozoic, one of the most successful phyla of marine invertebrates has been Echinodermata. Echinodermata was particularly successful throughout the Paleozoic, with class Crinoidea making up a majority of occurrences. The proportion of echinoderm occurrences that are crinoids declined massively at the end of the Permian and continued to decrease into modern day, never fully recovering. One of the factors thought to have been so important for crinoid success in the Paleozoic and their decreasing success throughout geologic time has been their propensity for success in shallow-marine environments, though crinoids also exist within deep-marine environments. This study seeks to …

Somatic Prosthetics For Planetary Resonance, Disha Dharesh Kumar R

Masters Theses

This thesis investigates how industrial design can transcend extractive technological paradigms in favor of relational interfaces that foster planetary attunement. Framing the climate crisis as a 'crisis of imagination', the research challenges the Western bifurcation of nature and culture by drawing on Indic cosmologies- which recognize stones, plants, and ecosystems as conscious at different levels and participants in a shared cosmic field. By synthesizing research in Biosemiotics, Quantum Information Pansycishm, and Neuroscience, the project redefines intelligence as a distributed, more-than-human phenomenon.

The research materializes as a speculative design artifact: a device that functions as a somatic prosthetic for planetary resonance. …

Quantifying Co2 And Ch4 Fluxes In A Semi-Arid Floodplain: Assessing Spatial And Temporal Drivers, Miles E. Kelsey

Earth and Planetary Sciences ETDs

Rivers transport sediment and carbon across Earth’s surface, and their floodplains can store carbon over decades to millennia, making them important to terrestrial carbon management. While soil carbon can persist long term, it may be released as greenhouse gases through processes like methanogenesis and heterotrophic respiration. Environmental controls on these fluxes remain poorly constrained across floodplains in different climate and geomorphic setting, but especially in semi-arid systems where measurements are limited. To address this gap, we quantified CO₂ and CH₄ fluxes along the Middle Rio Grande (New Mexico, USA) using 227 chamber measurements collected May to November 2025 at three …

Marine Geophysical Studies Of Coupled Tectonic And Sedimentary Processes At Active Plate Boundaries, Sarah R. Rysanek

Earth and Planetary Sciences ETDs

Deep-sea and convergent margin sedimentary systems preserve critical records of tectonic and climatic processes that shape Earth’s surface. This dissertation investigates source-to-sink sediment routing and forearc deformation to better constrain the interplay between sedimentary and tectonic processes, through investigations of a deep-sea fan system, and the forearc geomorphology offshore Nicaragua. In the Gulf of Alaska, we integrate ultra-long-offset and regional multi-channel seismic reflection data, multi-resolution bathymetry, and plate reconstructions to remap the Baranof Fan system. Results show that the fan is larger than previously recognized and constructed by two primary depocenters linked to distinct glacial sediment pathways, with accommodation space …

Constraining Magmatic Processes In The Central American Arc Using Melt Inclusion Vapor Bubble Analysis And Triple Oxygen Isotope Modeling And Exploration Of Volatile Contributions To The Production Of Continual Radio Frequency (Crf) Lightning Events, John M. Hamilton

Earth and Planetary Sciences ETDs

Magmatic volatiles are key to determining the processes happening in the subsurface that we cannot directly sample. Advances in measuring volatile and isotope contents from erupted volcanic samples have given us the ability to understand magmatic processes, mixing components that produce the bulk magma composition and potentially precursors to eruptive hazards, such as lightning.

Through analysis of melt inclusions that sample the melt at depth and triple oxygen isotope quantification of olivine crystals from multiple volcanic edifices, the three following studies display how I have utilized these analytical techniques to help unravel processes happening in the subsurface that lead volcanic …

2d And 3d Insights Into The Formation And Emplacement Of Martian Meteorites, Sierra Rhaye Ramsey

UNLV Theses, Dissertations, Professional Papers, and Capstones

Martian meteorites are the only samples currently available from Mars, making their study critical for understanding martian igneous processes. Despite extensive study over the last five decades, the formation (e.g., mantle sources, crystallization pressures), emplacement (e.g., intrusive versus extrusive), and shock histories of these rocks remain uncertain due to their innate lack of geologic context and limited petrologic tools calibrated for martian conditions. This dissertation analyzes a large suite of 22 igneous martian meteorites using complementary 2D and 3D analytical methods to better constrain the magmatic, emplacement, and shock processes responsible for their formation and ejection from Mars.

Chapters 2 …

Transboundary Groundwater Flow Between Niger And Nigeria In The Iullemeden Aquifer System, Gare Ambrose-Igho

UNLV Theses, Dissertations, Professional Papers, and Capstones

Groundwater is important in regions where water resources are not abundantly distributed such as arid and semi-arid regions. In many countries in Africa, groundwater serves as the most reliable source of water supply and supports over 50% of the African population. Groundwater is stored in underground water-bearing permeable rocks, rock fractures, or unconsolidated materials known as aquifers. Groundwater can be transboundary, meaning it crosses international political boundaries between two or more sovereign states. Transboundary aquifers are prone to overexploitation that depletes the groundwater resource and can cause a lowering of the water table and possible ground subsidence. Overexploitation in transboundary …

Preservation Of Sedimentary Rubidium Isotopic Signatures In Subduction Zones: Insights From The Schistes Lustrés Hp-Uhp Metasediments, Western Alps, Mary Clarich

UNLV Theses, Dissertations, Professional Papers, and Capstones

When oceanic plates bend and sink into the mantle at subduction zones, they carry sediments from the surface down into the mantle. The recycled sediments contain elements, that are depleted in the mantle, thereby influencing the composition of the mantle wedge and the formation of arc magmas, which are the building blocks of juvenile continental crust. However, it remains poorly constrained how much these elements, particularly fluid-mobile elements such as rubidium (Rb), are lost into fluids during metamorphic dehydration, and how much is transported to sub-arc depths where arc magmas are generated. Rubidium in subducting sediments is mainly hosted in …

Assessing The Relationship Between Subsurface Geology And Surficial Geomorphology: Remotely Predicting Geologic Features And Geohazards Using An Elevation-Trained Machine Learning Algorithm In The Northern Gulf Of Mexico, Allison L. Wing

Theses and Dissertations

This thesis evaluates the capacity to predict subsurface geologic features and submarine landslide susceptibility using surficial geomorphology derived from bathymetric elevation data in the Northern Gulf of Mexico. Quantitative geomorphic variables including slope, curvature, aspect, rugosity, geomorphons, and Bathymetric Position Index were generated from 30-meter digital elevation models and used as explanatory variables in presence-only Maximum Entropy models. Known locations of faults, pockmarks, mud volcanoes, hydrocarbon seeps, and landslides (particularly intact scarps) were used to train and validate predictive models through k-fold cross validation. Model performance was assessed using omission rates and AUC values. Results demonstrate that specific geomorphic signatures, …

Using Seafloor Geomorphology, Classification Schema, And Spatial Analysis To Predict Geologic Structures, With Applications For Mars, Emma Morgan

Theses and Dissertations

This study evaluated whether seafloor geomorphology can be used to predict subsurface fault locations along the Cascadia continental margin and explored whether such relationships can be transferred to Mars. Geomorphological classification schemas such as geomorphons, bathymetric position index (BPI), slope, rugosity, aspect, and curvature were derived from seafloor bathymetry data and used as predictor variables in maximum entropy (MaxEnt) models developed separately for Pre-Pleistocene, Pleistocene, Quaternary, and active fault datasets. Model performance ranged from AUC = 0.62 to 0.67, showing moderate predictive skill, with younger fault systems exhibiting stronger geomorphic associations. A secondary analysis showed a weaker but detectable relationship …

Evaluating The Spatial Relationship Between Geomorphology And Subsurface Structures On The Us Atlantic Margin With Applications To Other Terrestrial Planets, Andrea Caitlyn Stiles

Theses and Dissertations

High-resolution digital elevation models (DEMs) are widely available for terrestrial planetary bodies, but subsurface structural data remain limited. This research evaluated whether surface geomorphology could predict subsurface features, specifically faults and methane seeps, along the US Atlantic continental margin as an analog site. Faults were mapped with seismic interpretation and compared with quantitative geomorphic classifications derived from 100-m bathymetry including slope, aspect, rugosity, bathymetric position index, and geomorphon classes. Maximum-entropy modelling was used to predict fault occurrences from surface data. Results indicated that specific geomorphic landforms and slopes had the strongest control on fault presence, reflected in topographic expression of …

A Study Of The Links Between Denudation, Lithology, And Tectonics In The Tropical Andes, Helbert Garcia-Delgado

Dissertations - ALL

Landscape evolution in the tropical Northern Andes is governed by complex interactions between tectonic deformation, climatic shifts, and bedrock lithology. Standard geomorphic models often struggle to capture the full spectrum of these processes, particularly in active orogens where topographic steady state is frequently challenged by variable sediment dynamics and deep weathering. Understanding how these factors dictate landscape responses over different timescales is critical for interpreting the relationship between landscape evolution and surface processes of tropical mountain belts. This dissertation utilizes a combination of cosmogenic nuclide dating, numerical modeling, and subsurface borehole analysis to examine the structural, climatic, and lithological controls …

A Remote Sensing Approach To Identifying Zones Of Instability In Mine Tailings Impoundments Using Multi-Sensor Satellite Data, Arden K. Pierce

Honors Theses

Mine tailings impoundments are structures built to contain the chemical and sedimentary byproducts generated by ore extraction activities. In this common method of mining waste storage, the tailings can be pumped into containment ponds and held behind earthen embankments to prevent the release of hazardous substances into the surrounding environment. Monitoring environmental factors that influence the structural integrity of these impoundments is essential for identifying areas vulnerable to instability and failure. Soil moisture is a factor that can affect the stability of mine tailings impoundment structures. This study evaluates the relationship between satellite-derived soil moisture and surface deformation at mine …

Do National Parks Significantly Improve Air Quality?, Xinyi Liu

Honors Capstones

Healthy living has long been a goal pursued by individuals. In an era where PM2.5 concentrations and greenhouse gas levels are steadily increasing, many people prefer to live in areas with relatively lower levels of air pollution. National parks, as well-known protected areas, typically contain more vegetation and water resources, along with lower levels of human activity. This suggests two potential mechanisms: first, pollutant emissions are expected to be lower; second, vegetation, water bodies, and non-urban land may contribute to the removal or deposition of airborne pollutants, including particulate matter. In everyday experience, people often perceive the air to be …

Phase Equilibria Modeling Constraints On Seismic Velocity And Density For Mafic Granulites In The Athabasca Granulite Terrane, Western Canadian Shield, Olivia Wyllie

Geosciences Undergraduate Honors Theses

Samples of mafic granulite and eclogite from the Athabasca granulite terrane, thought to be representative of the lower continental crust, were analyzed via bulk geochemistry analysis and seismically modelled with Perple_X v.7.1.6. Modeled P-wave speeds, S-wave speeds, and densities for the samples were graphed by region and calculated for wet (1.00 wt.% H2O) versus dry (0.01 wt.% H2O) conditions at 460 °C and 648 °C. The samples were found to have higher median P-wave values than those determined by Rudnick and Fountain (1995; 7.4 km/s to 7.8 km/s, as compared to 6.9 km/s to 7.2 km/s). This indicates both a …

Sedimentary Provenance Of The Pliocene – Pleistocene Giant Foresets Formation, Offshore Taranaki Basin, Aotearoa New Zealand, Anurag Kulkarrni

Graduate Theses and Dissertations

Sediment input and dispersal in the Taranaki Basin, offshore New Zealand’s North Island, was influenced by a complex interplay of ocean currents and sea level fluctuations over the late Neogene. This period of time was recorded in the Pliocene-Pleistocene Giant Foresets Formation (GFF) that represents a rapid progradation of the western continental shelf into the basin. High sedimentation rates during this time were likely a major contributing factor to the emplacement of multiple, large-scale (up to ~3,500 km3) mass-transport deposits (MTD) that were caused by shelf and slope collapse within the GFF of similar scale to that of the well-studied …

Morphological Evolution And Sediment Budget Of A Flood-Tidal Delta On The Rio Grande Delta Plain: Bahia Grande, Texas, Usa, Aleen Pertuz Paz

Theses and Dissertations

The Isabel Delta is a recently formed flood-tidal delta within the restored Bahia Grande system on the Rio Grande Delta Plain, Texas, USA, where renewed tidal connectivity has created conditions for rapid sediment buildup and landform evolution. This study quantified morphological changes from 2008 to 2025 using satellite imagery. It assessed sediment retention by comparing the effective sediment discharge required to reproduce observed delta growth with field-based estimates of sediment supply derived from channel hydrodynamics, cross-sectional area, and suspended sediment concentration. The delta expanded steadily throughout the study period, with increases in bar, channel, and total surface area, and an …

On The Paleontology Of Belize, Alson Ovando

Electronic Theses and Dissertations

Paleontology can be considered an underrepresented and emerging area of science in Belize. A primary aim of this thesis is to provide a background of paleontology in Belize and present the first comprehensive study of Quaternary vertebrate fossils known from the country. Quaternary fossil sites across Belize include caves, rivers, and sinkholes. In addition to reviewing and assessing material from known sites, this thesis presents new information and discoveries that were made while investigating Belize’s Quaternary fossil record. This thesis also includes a geospatial model depicting ecoregions in Belize during the last glacial maximum. Overall, the results presented here demonstrate …

Machine-Learning Landslide Susceptibility And Runout Modeling In The Nolichucky River Gorge After Hurricane Helene, Grace Braver

Electronic Theses and Dissertations

Extreme rainfall from Hurricane Helene (September 2024) triggered widespread landslides across the southern Appalachian region, highlighting the need for rapid landslide susceptibility assessments that capture both landslide initiation and downstream runout. Traditional susceptibility models often focus solely on initiation zones, limiting their ability to identify which slopes will generate destructive landslides or where material will travel. This study addresses that gap by (1) integrating Geographic Information System (GIS)-based machine learning susceptibility modeling using ArcGIS Pro: Maximum Entropy (MaxEnt) and Random Forest-Based and Boosted Classification and Regression (FBBC) and (2) the U.S. Geological Survey (USGS) Grfin (Growth, Flow, and Inundation) runout …

Quantifying The Short-Term Hydrogeologic Responses Of Highway Construction In Hot Springs, Arkansas, Billy Jack Summerford

Graduate Theses and Dissertations

In late 2020, excavation for the Highway 5 Bypass in Hot Springs, Arkansas exposed seepage faces along roadcut walls. Groundwater levels at nearby wells decreased by up to 20.9 ft and have remained ~20 ft below pre-construction values on average. This study quantifies changes in storage in the unconfined aquifer within the Hot Springs thermal recharge zone associated with the seepage faces using a numerical groundwater model calibrated to pre-construction head at well ARb4. Model scenarios are used to evaluate whether construction-induced seepage or drought best explains the decrease from late 2020 to early 2021. The numerical groundwater simulation represented …