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Estimating Crustal Thickness In Northwest Louisiana Using The Receiver Function Method, Delton Samuel

LSU Master's Theses

I aim to constrain the crustal thickness of the Sabine Block in the Sabine Uplift region of northwest Louisiana, using the frequency domain receiver function deconvolution technique followed by H-κ stacking. The passive margin on the southern edge of the North American continent experienced an active tectonic history, including the spreading events that led to the formation of the Gulf of Mexico. A previous study proposed the Sabine Block is a residual fragment of Proterozoic orogenic origin; however, its full extent and geometry are up for debate. It is now overlain by thick sedimentary sequences ranging from ~4-6 km deposited …

Velocity Structure Of The Queen Charlotte Fault Across The 2013 Mw 7.5 Craig Earthquake Region, Lazaro Valentin Garza

WWU Graduate School Collection

Offshore southeastern Alaska and western Canada, the Queen Charlotte Fault (QCF) separates the Pacific (PA) and North American (NA) plates. Here the plate boundary experiences ~55 mm/yr of dextral slip accompanied by increasing fault obliquity from north to south. Among the historical M>7 earthquakes that have occurred on the QCF, two recent earthquake ruptures in 2012 and 2013 highlight the potential for seismic and tsunami hazard along the margin. Earthquake observations and geophysical imaging following the 2013 Mw7.5 Craig earthquake provided new insight into QCF crustal architecture, but also created new questions about how earthquake rupture dynamics are related …

Rapid Saline Permafrost Thaw Below A Shallow Thermokarst Lake In Arctic Alaska, Benjamin M. Jones, Mikhail Z. Kanevskiy, Andrew D. Parsekian, Helena Bergstedt, Melissa K. Ward Jones, Rodrigo C. Rangel, Kenneth M Hinkel, Yuri Shur

Michigan Tech Publications, Part 2

Permafrost warming and degradation is well documented across the Arctic. However, observation- and model-based studies typically consider thaw to occur at 0°C, neglecting the widespread occurrence of saline permafrost in coastal plain regions. In this study, we document rapid saline permafrost thaw below a shallow arctic lake. Over the 15-year period, the lakebed subsided by 0.6 m as ice-rich, saline permafrost thawed. Repeat transient electromagnetic measurements show that near-surface bulk sediment electrical conductivity increased by 198% between 2016 and 2022. Analysis of wintertime Synthetic Aperture Radar satellite imagery indicates a transition from a bedfast to a floating ice lake with …

Groundwater System Characterisation: Fortescue Alluvial Fan, Michael J. Donn, Olga V. Barron, Axel Suckow, Chris Turnadge, John A. Simons, Robert J. Paul, Christopher Schelfhout Dr

Natural resources commissioned reports

This report focuses on groundwater system characterisation in the region north of Newman, based on analysis of pre-existing data and data newly acquired during project activities. Groundwater system characterisation was an important research component supporting the assessment of managed aquifer recharge opportunities, using mine dewatering surplus generated (due to mining below the watertable) at large BHP Billiton Iron Ore operations in the eastern Pilbara mining zone, and aiming to support irrigated agriculture. The assessment area is located north of Ethel Gorge and covers the Upper Fortescue River floodplain and surroundings. The project added much knowledge to this largely ‘data-poor’ region, …

Geophysical Survey In Central North Dakota, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about a 2023–2024 Energy & Environmental Research Center (EERC) geophysical survey in central North Dakota to evaluate the feasibility of developing safe and permanent CO₂ storage in the project area. Describes the purpose of the survey and potential impact on local landowners.

Seismic Shadow Zone Investigation In The Upper Magma Reservoir Of The Yellowstone Caldera, Sarah Nolt-Caraway

Earth and Planetary Sciences ETDs

This study investigates whether the Yellowstone Caldera has enough melt to mute S-waves, creating a seismic shadow zone. Using a dense nodal deployment of ~650 stations, 7-9 earthquakes during the nodal deployment, and 21 broadband stations with 3,000-4,000 events per station; amplitude and noise maps, seismograms, and automatic phase picks probabilities from a deep learning model were analyzed to assess the potential role of melt, crustal attenuation, and noise in affecting body waves, particularly S-phases. The results are inconclusive, with unclear evidence whether observed amplitude decay is normal signal decay due to distance, noise-related, melt, or from scattering and intrinsic …

Whitewater Sound Dependence On Discharge And Wave Configuration At An Adjustable Wave Feature, Taylor A. Tatum, Jacob F. Anderson, Timothy J. Ronan

Geosciences Faculty Publications and Presentations

Stream acoustics has been proposed as a means of monitoring discharge and wave hazards from outside the stream channel. To better understand the dependence of sound on discharge and wave characteristics, this study analyzes discharge and infrasound data from an artificial wave feature which is adjusted to accommodate daily changes in recreational use and seasonal changes in irrigation demand. Monitorable sound is only observed when discharge exceeds ∼35 m³/s, and even above that threshold the sound-discharge relationship is non-linear and inconsistent. When sound is observed, it shows consistent dependence on wave type within a given year, but the …

Effects Of Discharge And Morphology On Fluvial Sound, Scott J. Gauvain

Boise State University Theses and Dissertations

Rivers, streams, and tributaries play a critical role in the global water cycle and their dispersion of freshwater is essential for widespread human consumption, crop irrigation, waste management, and hydropower generation. Currently, there is a need for innovative, non-invasive, and low-cost methods of surface freshwater discharge gauging. With careful site selection, recording the acoustics produced by streamflow could be used reliably and inexpensively to infer changes in local discharge. An important knowledge gap currently preventing the use of acoustics for stream gauging is the unknown relationships by which stream sounds depend on discharge and stream morphology. To address this, I …

Detection Of Subsidence In West-Central Florida Using Persistent Scatterer Interferometry And Near-Surface Geophysics, Tonian R. Robinson

USF Tampa Graduate Theses and Dissertations

This dissertation consists of three studies that employ Persistent Scatterer Interferometry (PSI, also known as PSInSAR) to better understand how subsidence in west-central Florida relates to underlying geological processes. In the first study, near-surface geophysical methods (Ground Penetrating Radar (GPR) and Electrical Resistivity (ERT)), terrestrial remote sensing applications (Light Detection and Ranging (LiDAR) and Structure from Motion (SfM)), and PSI were used to monitor the spatial and temporal behaviors of a suspected growing sinkhole in the Sandhill Boyscout Reservation, Hernando County, Florida. The survey area was located within and around a topographic low assumed to be the surface of the …

Uav-Based Quantification Of Dynamic Lahar Channel Morphology At Volcán De Fuego, Guatemala, Jerry C. Mock, Jeffrey B. Johnson, Armando Pineda, Gustavo Bejar, Amilcar Roca

Michigan Tech Publications, Part 2

This study quantified erosional and depositional processes for secondary lahars in Las Lajas drainage at Volcán de Fuego, Guatemala, during the rainy season from May to October 2021. Abundant pyroclastic material from ongoing eruptive activity is remobilized seasonally during heavy precipitation, which can impact infrastructure and populations living near Fuego. Our region of focus was in an agricultural zone 6 to 10 km from the summit, surveyed with an unoccupied aerial vehicle (UAV) quadcopter at monthly intervals. Imagery was processed into overlapping time-lapse structure from motion digital elevation models (DEMs). DEMs were differenced to find volumetric changes as a function …

A Simple Synthetic Example Of The Benefits Of Coincident Ground Penetrating Radar And Seismic Data Acquisition For Shallow Lunar Exploration, John Coonan

USF Tampa Graduate Theses and Dissertations

Both seismic and ground penetrating radar (GPR) methods have been used separately to image geophysical wave velocities and layering in the shallow lunar subsurface. However, uncertainties in the interpretation of both types of data persist. Collection of both types of data at a given site could reduce uncertainties in both the positions and nature of contacts. We illustrate the potential benefits of coincident data acquisition through a hypothetical case study of a lunar “lava tube” represented by a half-cylindrical vacuum-filled void within a solid rock medium. Propagation of both active-source seismic and muti-offset ground-penetrating radar waves is numerically modelled through …

Geophysical, Archaeological, And Geospatial Investigations At Presidio Los Adaes, 18th Century Capital Of Spanish Texas, Robert Linam

Electronic Theses and Dissertations

Presidio Los Adaes (16NA16), located in present day northwest Louisiana, served as the capital of Spanish Texas for much of the 18th century. Maps and historical documents provide architectural plans for the fort and other buildings on the site but differ in the size and location of several buildings. In 2009, a geophysical survey of the site with ground penetrating radar, magnetometry, electrical resistance, and electromagnetic induction showed good preservation of architectural foundations. Visual assessment of the maps and geophysical data, information from archaeological excavations, and spatial statistics suggests that the fort was originally built as specified by the architect, …

Quantifying Heterogeneity Along A Hillslope Using Seismic Refraction, Structure From Motion, And X-Ray Fluorescence In The Piedmont, South Carolina, Leah Topping

All Theses

The critical zone (CZ) is the life sustaining outer layer of the earth that spans from the top of unweathered bedrock to the tops of the trees. This dynamic zone is always evolving because a variety of chemical, physical, and biological processes transform bedrock into regolith, creating a spatially heterogeneous CZ architecture. This study aims to investigate the relationships between regolith thickness, seismic velocities, and chemical profiles as a function of slope position and it is hypothesized bedrock composition, fracture density, and foliation are the key factors controlling the physical heterogeneity in the top 1-2 meters of the CZ. To …

A Hidden Spider Web Of Roots: Utilizing Ground Penetrating Radar To Uncover Laterally Expansive Roots Of An Oak Tree, Megan Lapkoff

All Theses

Roots are critical to understanding tree health, subsurface biomass, and overall tree root stability. However, accessing tree roots is difficult and traditional methods used to quantify roots harm or kill the tree. Ground penetrating radar (GPR) provides a non-invasive way to characterize subsurface roots without harming the tree. GPR provides high-resolution data and the ability to collect data with high spatial coverage, making it an ideal tool for characterizing roots. GPR works by detecting contrasts in dielectric permittivity or electromagnetic (EM) velocity at interfaces between materials. Small scattering objects, like roots, generate predictable artifacts called diffraction hyperbolas. Diffraction hyperbolas will …

Geophysical Assessment Of Internal Erosion Damage At The Crawford County Levee, Samuel Ross Hokett

Graduate Theses and Dissertations

Levee failures during flooding events can result in catastrophic loss of life and property. Soil erosion during high water events is a primary cause of levee failures. Accordingly, this research focuses on the geophysical assessment of internal erosion damage in levees. This thesis presents a case study utilizing Capacitively Coupled Resistivity (CCR), Direct Current Electrical Resistivity Tomography (DC ERT), and Multichannel Analysis of Surface Waves (MASW) to assess internal erosion damage at the Crawford County Levee System in Van Buren, AR, that occurred during the 2019 Arkansas River flood. Geophysical surveys acquired included longitudinal CCR, DC ERT, and MASW lines …

Preliminary Site Assessment For Ground Monitoring Of A Complex Landslide Along I-40 In Roane County, Tennessee, Robert Mcsweeney, Ingrid Luffman Phd, Arpita Nandi Phd

Appalachian Student Research Forum

In-ground slope monitoring is an essential part of landslide early warning systems. Precise movement data from borehole monitors can detect emerging hazards near critical infrastructure. Typically, monitoring is done with inclinometers, but lower-cost alternatives have emerged which have yet to be tested in Tennessee. Time domain reflectometry (TDR) records magnitudes and depths of movements along a buried coaxial cable. When paired with a remote data logger, TDR can wirelessly transmit high resolution movement data in real time, making it promising for landslide early warning systems. Tennessee Department of Transportation (TDOT) has proposed a one-year feasibility study to test TDR for …

Geophysical And Archaeological Investigations Of Enslaved Peoples At Cannons Point Preserve, Georgia, Amy Sowers Collins, Eileen G. Ernenwein, Lindsey Cochran

Appalachian Student Research Forum

Geophysical and Archaeological Investigations of Enslaved Peoples at Cannons Point Preserve, Georgia

Amy Sowers Collins¹, Dr. Eileen G Ernenwein¹, and Dr. Lindsey Cochran², Department of Geosciences¹ and Department of Sociology and Anthropology², East Tennessee State University, Johnson City, Tennessee

Cannons Point Preserve at St. Simons Island, Georgia was the site for the 2022 East Tennessee State University archaeological field school. The study area was believed to have once housed enslaved peoples at the plantation. Ground penetrating radar (GPR) and magnetometry surveys were performed at the preserve. These geophysical surveys are a …

Slope Stability Risk Assessment In Urban Development, Eastern Tennessee Hillslope, Noah Hickerson, Arpita Nandi, David Jennings

Appalachian Student Research Forum

Landslides are a massive problem within the Appalachians causing large amounts of damage, and even loss of life. Urban development on the hill slope further destabilizes slope and accelerates failure. The objective of this project is to examine the slope stability condition at an urban community in eastern Tennessee and assess the relative risk in the area.

The first step included a digital survey of the area by collecting all available soil, geology, elevation, watershed, slope, drainage condition, stream, and building footprint data. This data was collected from a multitude of sources including but not limited to the United States …

Comparative Gpr Analysis Of Carbonate Strandline Deposits, Sydney Adelaide Richards

Theses and Dissertations

The Bahamas Island archipelago grows by the precipitation and secretion of calcium carbonate. A majority of this growth is by lateral accretion of shoreline sedimentary deposits. Previous research is not clear on whether the growth is largely due to eustasy, sediment input from catastrophic events, or a combination of both. The Bahamas is an ideal location for studying Holocene carbonate generation and deposition, but there is limited research on the analysis of strandlines in relation to lateral accretion. Carbonate strandline deposits are commonly classified as low-energy beach ridge deposits. Previous researchers have primarily focused on ooid shoals and subtidal regions. …

Stratigraphic Architecture Of Pozuelo Mounds As Revealed By Earth Resistivity Tomography, Caeli Connolly

Honors College

This study is a geoarchaeological analysis using earth resistance tomography (ERT) surveys of two of four mounds at Pozuelo (Formative Period, cal yr 3000 BP) in the Chincha Valley of coastal, southern Peru. Layers identified in the subsurface were to determine the presence or absence of regional continuity between the mounds. This effort is part of a larger investigation examining the paleoenvironmental setting of the site, and its influence on site location and use. Ten earth resistance tomography profiles were collected using an ABEM Terrameter LS2 and 81 pin array. These profiles were then topographically corrected using topographic survey data …

The Role Of Volatile Enrichment In The Radiogenic Heating And Thermal Evolution Of Rocky Exoplanets, Ula Jones, Asmaa Boujibar

WWU Honors College Senior Projects

Internal heating in terrestrial planets is a fundamental physical process controlling the internal structure of a planet, mantle convection, volcanic activity, and the generation of magnetic fields. Internal heating results from various processes including radioactive decay and accretional energy, as well as additional irradiation and tidal heating in planets with short orbital periods. The largest long-term heat source for terrestrial planets is radioactive heating, especially from the decay of uranium (U), thorium (Th), and potassium (K) isotopes. K is a moderately volatile element, while U and Th are refractory elements; during planetary accretion volatiles are depleted relative to refractory elements, …

Design Of A Non-Destructive System For Arctic Permafrost Detection Via High Frequency Electromagnetic Induction, Gray Dominic Thurston

Theses and Dissertations

Electromagnetic induction (EMI) sensors have been utilized in the past by the United States Army Corps of Engineers as a method of detecting unexploded ordnance (UXO). Recently, an EMI instrument was constructed that extended the traditional EMI frequency range from 100 kHz to 15 MHz to aid in the detection of nonmetallic ordnance, landmines, and improvised explosive devices. Building on this research, the iFROST mapper project aims to use the same high-frequency (HF) EMI technique to characterize arctic soil and subsurface permafrost deposits. Based on a device used by the US Army for UXO detection, an HF EMI instrument was …

Silicon And Oxygen In Earth’S Core: Applications Of Machine Learning To Metal-Silicate Equilibria And Core Formation, Ruben Keane

WWU Honors College Senior Projects

Within Earth’s core, light elements (Si, O, C, S, N, H) are known to make up a small fraction of the total mass of the core with respect to heavy elements. The degree to which these elements exist in the cores of terrestrial planets have geophysical and geochemical implications, most notably the presence of core convection and a geodynamo, thermal conductivity within the core, and core temperature. Comparison of the composition of chondrites to Earth’s mantle composition and the Preliminary Reference Earth Model have given an estimation of about 10 % light elements in Earth’s core. The concentrations of each …

Oh The Places Snow Blows: Observations And Impacts Of Snow Redistribution On Arctic Sea Ice, David Clemens-Sewall

Dartmouth College Ph.D Dissertations

Arctic sea ice has declined dramatically due to climate change. This decline impacts Arctic communities, ecosystems, international trade, and the world's climate. However, due to uncertain physical processes, climate models generally do not capture the severity of the observed decline---adding uncertainty to projections of future climate change. A major uncertainty in the Arctic sea ice component of climate models is how much heat passes through the snow on top of the ice in the winter. This heat flux controls how much ice grows each winter, impacting how much ice survives the summer melt. Snow is an excellent thermal insulator (about …

Application Of The Hvsr Technique To Map The Depth And Elevation Of The Bedrock Underlying Wright State University Campus, Dayton, Ohio, Devika L. Ghuge

Browse all Theses and Dissertations

Estimating sediment thickness and bedrock surface geometry is critical for many hydrogeologic studies. The horizontal-to-vertical spectral ratio (HVSR), a passive seismic method is a unique, non-invasive technique for speedily estimating bedrock depth. To record ambient seismic noise, the H/V method employs a single broadband three-component seismometer. A field assessment was conducted on the Wright State University Campus in Dayton, Ohio, to determine the depth (z) and elevation of the bedrock. Data were collected at 60 different locations. A known value for the depth of bedrock on campus was determined using the log from a local water well available from the …

Investigating Elastic Deformation Induced By Surface Loads On Planetary Bodies, Ashlesha Khatiwada, Hilary Martens, Donald F. Argus

Graduate Student Theses, Dissertations, & Professional Papers

Planetary bodies, including the Earth, deform when there is a redistribution of surface load. In this thesis, I conduct three independent projects related to surface loading, two of which investigate methods related to the modeling of surface loading and one which seeks to catalog the displacement responses of other planetary bodies to a surface load.

The first project aims to compare four methods for modeling the elastic loading response of the Earth: a homogeneous, non-gravitating, half-space method; a homogeneous, gravitating, spherical method; a homogeneous, non-gravitating spherical method; and a radially stratified gravitating spherical method. Many studies have focused on computing …

Evaluating The Sensitivity Of Crustal Deformation To Bedrock Hydrology In A Mountain Watershed, Brett J. Oliver

Graduate Student Theses, Dissertations, & Professional Papers

We evaluate the sensitivity of Earth's elastic deformation to groundwater hydraulic diffusivity using coupled groundwater and elastic deformation models. Seasonal changes in terrestrial water storage cause deformation to the Earth’s crust and deeper interior that is within the observational capacity of GPS instruments. We couple finite difference groundwater simulations with geodetic forward models of crustal displacement to investigate the ability of geodetic deformation to constrain bedrock hydrologic properties. We use MODFLOW-2005 to simulate seasonal changes in groundwater flow and storage, and then use the LoadDef elastic deformation model to forward model surface displacement caused by the change in terrestrial water …

Dataset For Whitewater Sound Dependence On Discharge And Wave Configuration At An Adjustable Wave Feature, Taylor Tatum, Jacob Anderson

Boise State University Infrasound Data Repository

Stream acoustics has been proposed as a means of monitoring discharge and wave hazards from outside the stream channel. In order to better understand the dependence of sound on discharge and wave characteristics, this study analyzes discharge and infrasound data from an artificial wave feature. This feature, known as Boise Whitewater Park, is adjusted to accommodate daily changes in recreational use and seasonal changes in irrigation demand. Significant sound is only observed when discharge exceeds ~35 m^3/s, and even above that threshold the sound-discharge relationship is non-linear and inconsistent. When sound is observed, it shows consistent dependence on wave type …

Reprocessing Groundwater Resistivity Surveys In The Lower Mesilla Basin, New Mexico, And Texas, Leslie Bernal

Open Access Theses & Dissertations

The Mesilla Basin is part of the Rio Grande Basin System. Its northern boundary is definedby the Doña Ana Mountains in New Mexico and to the south by Sierra San Blas, Sierra Almirez, and Sierra La Candelaria in Mexico, where the basin changes its name to Conejos-Médanos. It supplies water for irrigation and public use to the cities of Las Cruces, NM, El Paso, TX, and Ciudad Juárez, Mexico. The southern part of the basin in the U.S. territory, known as the Lower Mesilla Basin, is bounded to the east by the Franklin Mountains, to the west by the Potrillo …

Exploring The Effects Of Tree Roots On Infiltration Process, Nazife Onaral

Masters Theses

Effects of the root structures on soil infiltration dynamics are not clearly defined. Imaging the complex tree root structures and movement of water through the root ball is a challenging task to achieve without damaging the trees and roots by conventional methods. Commonly used methods are invasive, labor-intensive, and not easily accessible. Ground Penetrating Radar (GPR) has commonly been used to characterize soil profiles and it can be a reliable tool to map complex root structures with a novel high-resolution circular data collection technique. Electrical resistivity tomography (ERT) is another reliable geophysical method to image infiltration processes by the change …