Geophysics and Seismology Commons^™

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 …

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 …

Comprehensive Analysis Of Krauklis Waves And Long Period Seismic Events In Fluid-Filled Fractures Via Integrated Physical And Numerical Modeling, Sananda Ray

Dissertations, Master's Theses and Master's Reports

Long-period (LP) seismic events, commonly recorded in volcanic and hydrothermal environments, are widely attributed to the resonance of fluid-filled fractures and the excitation of Krauklis waves along the solid-fluid interface. These low-velocity, dispersive waves are sensitive to both fluid dynamics and fracture geometry, offering critical insights into subsurface fluid transport, fracture evolution, and seismic source processes. Despite robust theoretical treatments, experimental validation under realistic geological conditions has remained limited. To address this, I aimed to develop a series of laboratory-based experimental models that systematically investigate the key physical mechanisms driving LP signal generation. In the first set of experiments, I …

Fault Box Modeling Of Dip Slip Faults: A Framework For Fault Box Design And Future Studies, Hailey Pressnell

Master's Theses

The behavior of soils during surface fault rupture is a serious concern in the planning and design of infrastructure that may be located within or near a fault zone. Challenges associated with developing mitigation measures for surface fault rupture include the uncertainty of fault rupture and the variability of fault behavior. Current analytical procedures define surface fault rupture according to the type of fault movement (strike slip, normal or reverse), the amount of displacement on the fault, and the mechanics of the material overlying the fault. The purpose of this thesis is to reconfirm analytical solutions and gain a better …

Evaluating The Causes Of Land Subsidence On The U.S. Mid-Atlantic Coast Measured With Insar, Jordan Leigh Diprima

Honors Theses and Capstones

Land subsidence is a frequently overlooked geologic hazard that is caused by natural processes and anthropogenic stressors. The goal of this study is to quantify vertical land motion (VLM) on Long Island, New York and Virginia’s Eastern Shore and evaluate the potential causes of subsidence. The causes considered in this work are glacial isostatic adjustment, groundwater extraction, infrastructure loading, and land cover. This study utilizes interferometric synthetic aperture radar (InSAR) satellite data from Sentinel-1 to calculate linear VLM trends from 2017 to 2023. Datasets for each hypothesis were qualitatively compared to VLM data. Subsidence rates in both regions were found …

A Hybrid Method For Source Direction Finding With Radio Frequency Interference And Gaussian White Noise, Yanming Zhang, Wenchao Xu, Antonios Argyriou, A. Long Jin, Tianquan Tang, Peifeng Ma, Lijun Jiang, Steven Gao

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a hybrid data-driven method, termed moving average-Hankel-dynamic mode decomposition (MAHankDMD), for joint direction of arrival (DOA) and frequency estimation in environments affected by both radio frequency interference (RFI) and Gaussian white noise. The proposed approach integrates two key components: (1) a moving average-DMD filter that effectively mitigates Gaussian white noise and separates RFI from the source signal, and (2) a Hankel-DMD method that accurately estimates the DOA of the filtered signal and associates it with the corresponding frequency. The moving average-DMD stage first enhances the signal-to-noise ratio and improves the robustness of the estimation process through noise …

Provenance Of The Uppermost Carboniferous–Lower Triassic Sandstones, Bogda Mountains, Nw China: Implications On The Late Paleozoic Tectonic History Of The Southern Central Asian Orogenic Belt, Sixuan Wu

Doctoral Dissertations

"The Permian-Triassic period represents a significant but insufficiently understood tectonic transition stage in the southern Central Asian Orogenic Belt (CAOB) between the Paleozoic continental amalgamation and Cenozoic orogenic reactivation. This study integrates fieldwork, petrographic, and detrital zircon geochronological data to document the trend of depositional environments, framework grain compositions, and dates of detrital zircon grains of the uppermost Carboniferous–Lower Triassic sandstones from three study areas in Bogda Mountains, the greater Turpan-Junggar basin, NW China, to decipher the spatial and temporal changes in the provenance lithology and area and reconstruct the unroofing history of the southern CAOB.

In the first part …

Fiber Optic Distributed Acoustic Sensing For Surface Wave Inversion In Terrestrial And Marine Environments, Constantine Coclin

Open Access Master's Theses

The use of distributed acoustic sensing (DAS) has gained popularity for a variety of seismic sensing applications due to its capability to sense broadband frequency ranges on spatial scales unattainable with conventional point sensors. The ability to sense and characterize vibrational surface waves in the near-surface can provide valuable information about the subsurface structure of an environment. The objective of this study is to evaluate the use of DAS to sense surface wave propagation for the multi-channel analysis of surface waves (MASW) methodology, such that a sub-surface shear wave velocity profile can be obtained in both a terrestrial and near-shore …

Applications Of Uav In Landslide Research: A Review, Boneng Chen, Jeremy Maurer, Weibing Gong

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Uncrewed aerial vehicles (UAVs), commonly known as drones, have gained significant popularity in landslide research due to their operational flexibility, near real-time planning capabilities, cost-effectiveness, high-resolution data outputs, and enhanced safety. This review aims to provide an analysis of UAV-based landslide investigation methodologies and their applications. It begins with an examination of UAV platforms and UAV-equipped sensors employed in landslide research, evaluating their advantages and limitations to guide appropriate platform and sensor selection. The review then explores UAV applications across three primary landslide investigation domains: landslide mapping, landslide monitoring, and landslide hazard assessment, highlighting some representative achievements in each domain. …

Agu's Scientific Legacy, Eileen E. Hofmann, Tissa Illangasekare, Francis A. Macdonald, Michael J. Mcphaden, Anne Meltzer, Imke De Pater, Susan J. Roberts, Anne M. Thompson

OES Faculty Publications

The AGU community is a resource for insights into how past research has influenced today's science and will continue to inform the Earth and Space sciences of the future. To capture the voices and opinions from this community, three interviews were held at the 2024 AGU Meeting and broadcast on AGUTV. The interviews with Richard Alley, Susan Lozier and Rana Fine aligned with the daily themes for the 2024 AGU Meeting. The interviewees shared insights from their experiences about the importance of science and how science has shaped their careers and society.

Evaluating Tropospheric Delay Modeling For Enhanced Geospatial Accuracy, Adeyinka Olaoluwa Olaseinde

Masters Theses

Interferometric Synthetic Aperture Radar (InSAR) is a vital technique for monitoring ground surface deformation across large spatial scales. However, variability in atmospheric water vapor, pressure, and temperature introduces tropospheric delays that can significantly affect measurement accuracy. These delays are often corrected using outputs from numerical weather prediction (NWP) models. RAiDER, an open-source Python package, facilitates this by estimating tropospheric delays using models such as the High-Resolution Rapid Refresh (HRRR). Previous studies have shown that weather model–based corrections can substantially reduce atmospheric noise in InSAR data but also highlight persistent residual errors, especially at spatial scales smaller than the model grid …

Overall Tropospheric Noise Over The St. Louis Using Isce And Fringe Processing, Maryann Lee

Masters Theses

Interferometric Synthetic Aperture Radar (InSAR) is a satellite-based technique that is used to measure various aspects such as ground deformation, earthquakes, volcanic activity, and motions of glaciers. Although the technique has proved very useful, measurements errors such as ionospheric and tropospheric noise, and deformation often cause problems with making precise measurements. InSAR is a tool used in geodesy that is used to measure the change of surface deformation over time through a series of repeated SAR acquisitions. These errors in the acquisitions occur from factors of signal decorrelation, atmospheric delays, and phase unwrapping errors that affect the accuracy and precision …

Cold Atmospheric Plasma Induced Degradation Of Organophosphate Pesticides On Kevlar Swatches, Ta Chun Lin, Victor Somtochukwu Mbanugo, Boluwatife Stephen Ojo, Yue-Wern Huang, Marek Locmelis, Frank Daoru Han

Biological Sciences Faculty Research & Creative Works

Cold atmospheric plasma (CAP) was evaluated for degrading organophosphate pesticide (OP) residues (acephate, malathion, and dimethoate) from Kevlar fabrics. Fourier transform-Infrared (FTIR) spectroscopy, scanning electron microscope (SEM) imaging and tensile strength testing confirmed that CAP treatment preserved Kevlar's structural integrity and mechanical properties. Results show degradation efficiency increased with higher power, shorter discharge gaps, and longer exposure duration. Hyperspectral imaging supported the detection of plasma-induced spectral changes, reinforcing the presence of reactive species. The strong oxidative potential of CAP facilitated the rapid breakdown of OPs into nontoxic byproducts. These findings demonstrate the potential of CAP as a portable, energy-efficient solution …

Microbial Diversity And Biogeochemical Interactions In The Seismically Active And Co2-Rich Eger Rift Ecosystem, Daniel Lipus, Zeyu Jia, Megan Sondermann, Robert Bussert, Alexander Bartholomäus, Sizhong Yang, Dirk Wagner, Jens Kallmeyer

College of Life Sciences Faculty Papers

The Eger Rift subsurface is characterized by frequent seismic activity and consistently high CO2 concentrations, making it a unique deep biosphere ecosystem and a suitable site to study the interactions between volcanism, tectonics, and microbiological activity. Pulses of geogenic H2 during earthquakes may provide substrates for methanogenic and chemolithoautotrophic processes, but very little is currently known about the role of subsurface microorganisms and their cellular processes in this type of environment. To assess the impact of geologic activity on microbial life, we analyzed the geological, geochemical, and microbiological composition of rock and sediment samples from a 238 m deep drill …

Finite-Difference Time-Domain Simulation For Interpreting Regional Infrasound Arrivals And Estimating Propagation Path Effects, Jesse Howard

Earth Sciences Theses and Dissertations

New full-wave infrasound simulation tools were developed based on an optimized finite-difference time-domain solution of 2D axisymmetric linear and nonlinear fluid dynamic equations. These tools were applied to estimate propagation path effects and enhance phase interpretation for regional infrasound arrivals. Middle-atmosphere full-wave predictions for a range of idealized atmospheres show that shadow zone arrivals and fast and slow arrival pair components from multiple ducts can be delineated using a combination of full-wave modeling and geometrical acoustics. Relationships between phase velocity and effective sound profile were established for each arrival type. Implications for source characterization were that amplitude and spectrum variation …

Glacial Erosion Rates From The Last Glacial Maximum To Present In Southern Patagonia (50°S), Anastasia Fedotova

Earth Sciences Theses and Dissertations

Over the past few decades, the notion of exogenic processes (e.g. weathering, erosion) contributing to mountain building rather than destruction has become increasingly supported through both direct observations and modeling. As a result, the details of the link between erosion, and therefore climate, and the tectonic evolution of mountain ranges, have progressively become established. One of the key observations emerging from the climate-tectonic debate has been the role of glaciers as powerful landscape sculptors, sensitive to climate signals. The reconstruction of glacial environments evolution and the recovery of patterns of glacial erosion over time have proven key to understanding feedbacks …

Sedimentary Characteristics Of Flood Deposits In Coastal And Fluvial Environments: Examples From Washover Fans (North Carolina, Usa) And Floodplain Deposits (Mississippi, Usa), Shara Gremillion

Dissertations

Extreme flooding from severe and prolonged meteorological events and / or overbanking rivers are some of the most deadly and expensive disasters globally, impacting millions of lives, the environment, and property. People living in vulnerable areas, such as near coasts and rivers, are the first to be impacted with effects of these flood hazards. Scientific studies and their results can aid communities and officials in planning and preparing for those flood impacts. In this three-part study, flood impacts from coastal storms in North Carolina, and flooding along the Mississippi River (MSR) in the state of Mississippi, USA are assessed from …

Α-Quartz Plastic Strength Investigation Via Diffraction Experiments On Novaculite Using A D-Dia And Elastic Plastic Self-Consistent Interpretation, Denali Jivanjee Medina

UNLV Theses, Dissertations, Professional Papers, and Capstones

The plastic response of experimentally deformed quartz provides insight into the strength of ductile shear zones that has implications for tectonic, lithospheric, and ore deposit models. We present a suite of 15 uniaxial deformation experiments on Arkansas novaculite conducted in a DDIA apparatus with in-situ synchrotron x-rays. Experimental temperatures range from 25 C to 1334 C with pressures between 1.39 GPa and 3.1 GPa, and strain rates between 1x10-5 s-1 and 9x10-6 s-1. Macroscopic sample strain ranges from 3% to 24%. d-spacings from the (101), (110), (200), (201), and (112) lattice planes were measured, producing lattice strain up to ~5%. …

Mapping Amis Mill In Rogersville, Tennessee In The 1780s Using Geophysical Methods And Remote Sensing, Amy Collins

Electronic Theses and Dissertations

Geophysics and remote sensing were used at the Amis Mill and Homesite to determine the location of structures during the 1780s. Areas of interest were surveyed using shallow geophysical and remote sensing techniques including the orchard, horse pasture, original kitchen on the east side of the house, the west side of the house, plowed field, store site, and cemetery. After analyzing the results of the geophysical surveys and remote sensing, 22 sites were chosen to test inside and outside potential features. A large rectangular feature, possibly a tavern with a cellar, was discovered. Four other features were identified, three of …

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 …