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Articles 1 - 30 of 663
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Hvsr-Based Resonance Analysis And Fault Zone Characterization In The El Paso Region, Alexandro Dominguez
Hvsr-Based Resonance Analysis And Fault Zone Characterization In The El Paso Region, Alexandro Dominguez
Open Access Theses & Dissertations
Horizontal to Vertical Spectral Ratio (HVSR) analysis offers an efficient method for characterizing near-surface structure, resolving sediment thickness, and identifying fault-controlled basin geometry in regions with strong impedance contrasts. This study applies HVSR techniques to continuous ambient-noise recordings collected across the El Paso region, a tectonically active segment of the southern Rio Grande Rift where accurate subsurface mapping is essential for seismic hazard assessment. Ambient-noise windows were processed, spectrally smoothed, and stacked to obtain stable HVSR curves, from which fundamental resonance frequencies and corresponding sediment-thickness estimates were derived. Spatial patterns in these resonance frequencies reveal pronounced basin asymmetry, abrupt lateral …
Enhancing The Mechanical Strength Of Soy-Based Polyurethane Adhesives Through Incorporation Of Schiff Based Diols, Yashkumar N. Patel
Enhancing The Mechanical Strength Of Soy-Based Polyurethane Adhesives Through Incorporation Of Schiff Based Diols, Yashkumar N. Patel
Electronic Theses & Dissertations
Recent advancements and trends in eco-efficient bio-based adhesives are explored in recent years. “Eco-efficient” refers to being effective both environmentally and economically. In this study, soy-based polyurethane (PU) adhesives were reinforced with vanillin-derived Schiff base diols (VB and VH) to improve mechanical strength and thermal stability. Two diols synthesized from vanillin and aliphatic diamines butanediamine (BDA) for VB, hexanediamine for VH were incorporated at 5, 10, and 15 weight percentages (wt.%) into a soy-based PU network cured with methylene diphenyl diisocyanate (MDI). Mechanical testing on bonded oak wood showed that adding these crosslinkers noticeably increased adhesive strength. Optimal performance occurred …
Comprehensive Evaluation Of Co₂ Eor Numerical Modeling In The Clinton Sandstone Of The Appalachian Tri-State Region Using Compositional Reservoir Simulation (Cmg Gem), Bushra Aref Alqattan
Comprehensive Evaluation Of Co₂ Eor Numerical Modeling In The Clinton Sandstone Of The Appalachian Tri-State Region Using Compositional Reservoir Simulation (Cmg Gem), Bushra Aref Alqattan
Graduate Theses, Dissertations, and Problem Reports (ETD)
ABSTRACT
The Clinton Sandstone of the Appalachian Basin represents a mature hydrocarbon-producing formation with potential for carbon dioxide (CO₂) enhanced oil recovery (EOR). This study develops a compositional reservoir simulation model using the CMG software suite (WinProp, Builder, and GEM) to evaluate the performance of CO₂ injection in improving oil recovery within the Clinton formation.
A three-dimensional reservoir model was constructed using representative geological and petrophysical properties consistent with those of the Clinton Sandstone. Fluid behavior was modeled using a compositional equation-of-state (EOS) approach to accurately capture phase behavior, miscibility development, and CO₂–oil interactions under reservoir conditions. Injection scenarios were …
Structural Framework And Tectonic Implications From Field Investigations In The Ramelau Mountains, Timor-Leste, Tanner A. Nielsen
Structural Framework And Tectonic Implications From Field Investigations In The Ramelau Mountains, Timor-Leste, Tanner A. Nielsen
Theses and Dissertations
Recent advances in petroleum exploration off the southern coast of Timor-Leste and emerging mineral discoveries onshore have underscored the need for a more comprehensive structural understanding of the nation's geology. Although new structural models have been proposed for other parts of Timor, limited progress has been made toward developing detailed models for the Ramelau Mountains, which presents the highest structural relief of the Timor Ranges. Previous mapping in this area has been largely reconnaissance in nature and focused primarily on surface bedrock geology. This study presents a new 1:62,500-scale geologic map and a geometric structural analysis of the Ramelau region …
For 600,000 New Yorkers, Toxins Are In Their Tap Water: A New York Focus Analysis Of State Inspection Data Shows Key Toxins Are In Public Water Systems From Long Island To The Adirondacks, Posing Risks For Cancers And Other Diseases. Millions Are Being Spent To Fix Problems, But Even Well-Planned Efforts Have Faced Delays. Poorer Towns Wonder If They Can Afford To Fix The Problem., Shuchi Shah, Hayden Betts, Aurora Martinez, Rebecca Mccray
For 600,000 New Yorkers, Toxins Are In Their Tap Water: A New York Focus Analysis Of State Inspection Data Shows Key Toxins Are In Public Water Systems From Long Island To The Adirondacks, Posing Risks For Cancers And Other Diseases. Millions Are Being Spent To Fix Problems, But Even Well-Planned Efforts Have Faced Delays. Poorer Towns Wonder If They Can Afford To Fix The Problem., Shuchi Shah, Hayden Betts, Aurora Martinez, Rebecca Mccray
Capstones
The story stems from an analysis of New York State data on drinking water contaminants. The state inspection data shows key toxins are in public water systems from Long Island to the Adirondacks, posing risks for cancers and other diseases. Millions are being spent to fix problems, but even well-planned efforts have faced delays. Poorer towns wonder if they can afford to fix the problem.
A Geological And Geochemical Study Of The Philipsburg Mining District, Granite County, Montana, Celine M. Beaucamp
A Geological And Geochemical Study Of The Philipsburg Mining District, Granite County, Montana, Celine M. Beaucamp
Graduate Theses & Non-Theses
The Philipsburg district, renowned for its rich mining history, has contributed significantly to Montana's mineral production, ranking as the state's second-most productive district. Active from 1865 to the 1980s, it yielded an impressive array of Ag (50-60 million oz), with notable outputs of Au, Zn, Pb, Cu, and battery-grade MnO2. The district features Cordilleran polymetallic veins, some of which are along bedding in Mississippian and Devonian limestone, and others are steeply dipping quartz veins in silicate-rich sedimentary rocks and in the Philipsburg batholith. The veins exhibit a district-wide mineral zonation, marked by Cu- and Ag-rich ores near granite porphyries, with …
The Depositional Environment Of The Triassic Cow Branch Formation, Dan River Basin Of Virginia And North Carolina Through Petrographic Study And Geochemical Analysis, And In Relation To Taphonomic Processes And Vertebrate Morphology, Gina M. Workman
All Graduate Reports and Creative Projects, Fall 2023 to Present
The Upper Triassic Cow Branch Formation of the Dan River Basin, located in southern Virginia and northern North Carolina, has long captivated generations of geoscientists. Since the 1970s, researchers have sought to unravel the mystery surrounding the depositional environment of this ancient lake system. This world-class lagerstätte hosts a diverse assemblage of fossil fauna and flora, with a notable preservation bias toward fossil vertebrates, most prominently the archosauromorph, Tanytrachelos ahynis. The geology of the Cow Branch strata continues to evoke a persistent question: Are these sediments representative of a shallow or deep lake?
I undertook a petrographic and geochemical study …
Trans-Tensional Chaos In Southeastern Death Valley: Geologic Mapping And Geochronology Of The Miocene China Ranch Beds, California, Sydney Beltran
Trans-Tensional Chaos In Southeastern Death Valley: Geologic Mapping And Geochronology Of The Miocene China Ranch Beds, California, Sydney Beltran
Electronic Theses and Dissertations Archive
This study investigates the sedimentary record of the Miocene China Ranch beds and structural evolution of the China Ranch Basin (CRB) in southeastern Death Valley, California. Geologic mapping and geochronological studies of the China Ranch beds document progressive sedimentary fill of a transtensional basin developed at the tectonic intersection of several strike- slip faults, including the right-lateral Sheephead and Grandview fault zones, and several left- lateral fault zones. New and existing geochronology from 40Ar/39Ar of plagioclase from volcanicash beds, and new detrital zircon U-Pb analysis of volcaniclastic sandstones constrain the depositional history of the China Ranch basin from approximately <11.2 Ma to >6.8 …11.2>
Integrating Satellite Observations And Modeling Approaches To Study Tectonic And Land Surface Hazards, Jeng Hann Chong
Integrating Satellite Observations And Modeling Approaches To Study Tectonic And Land Surface Hazards, Jeng Hann Chong
Earth and Planetary Sciences ETDs
The increasing availability of Earth observation satellites, such as SAR and optical platforms, has improved our ability to study the ground deformation processes during, after, and leading up to these natural hazards, such as earthquakes and debris flows. In this dissertation, I analyze satellite geodetic interseismic velocities across the Rakhine-Bangladesh megathrust and the influence of having realistic modeling assumptions for subduction zones to better constrain seismic hazard. I also examined changes in post-fire debris flow likelihood four years after the 2020 Lake Fire in Southern California using a suite of satellite data and field observations. Together, these studies highlight how …
Mechanisms Of Gold Enrichment In Seafloor Massive Sulfide Deposits: A Study On The Higashi-Aogashima Hydrothermal Field, Claudia Martinez
Mechanisms Of Gold Enrichment In Seafloor Massive Sulfide Deposits: A Study On The Higashi-Aogashima Hydrothermal Field, Claudia Martinez
UNLV Theses, Dissertations, Professional Papers, and Capstones
The study of Seafloor Massive Sulfides (SMS) deposit formation is vital for assessing both the economic potential and environmental risks posed by future marine mining projects. Metal-rich SMS deposits form in hydrothermal vent systems within tectonically active regions, such as back-arc basins, where faults enhance crustal permeability, enabling fluid migration driven by magmatic heat sources at depth in the crust. Currently our understanding of SMS formation processes is based on bulk-rock geochemical and isotopic data, lacking the necessary spatial and temporal resolution to understand ore forming processes. As a result, critical gaps remain in understanding the exact mechanisms responsible for …
Automated Grain-Matrix Segmentation In Photomicrographs Of Clastic Sedimentary Rocks Using Neuro-Visual Algorithms, Rajdeep Das
Automated Grain-Matrix Segmentation In Photomicrographs Of Clastic Sedimentary Rocks Using Neuro-Visual Algorithms, Rajdeep Das
Doctoral Theses
Sediments and sedimentary rocks, covering almost sixty-five percent of exposed earth’s surface, contain features that allow us to interpret ancient depositional environments, and their role in the evolution of life on earth. Study of sedimentary rocks is also relevant to exploration of geo-economic resources including petroleum, ore minerals, and groundwater as well as research in environmental geology, anthropological studies, and the bi-directional relation of man and environment. One of the important and crucial steps in this study of the detrital sedimentary rocks like sandstone, is to know the size and shape of the grains/clasts (fragments of different minerals or rocks), …
Glacial Lakes Segmentation Using Multispectral Remote Sensing Data And Deep Learning Models, Debankan Das
Glacial Lakes Segmentation Using Multispectral Remote Sensing Data And Deep Learning Models, Debankan Das
Master’s Dissertations
The identification and delineation of glacial lakes through segmentation is crucial for tracking glacial changes and evaluating potential dangers from sudden flood events (GLOFs). These floods can severely impact populated areas and man-made structures downstream. Recent advances in high-quality satellite imagery have sparked increased attention toward using advanced machine learning methods, particularly deep learning, to enable precise and automated glacial lake detection. In this study, we explore the effectiveness of deep learning-based pointwise semantic segmentation for glacial lake mapping using multisource remote sensing imagery, including both optical and synthetic aperture radar (SAR) data. We experiment with a novel stack combination …
Hyperspectral Remote Sensing Of Potential Mineral Resources At Elephant Mountain, Interior Alaska, Khawaja Ahad Javed
Hyperspectral Remote Sensing Of Potential Mineral Resources At Elephant Mountain, Interior Alaska, Khawaja Ahad Javed
Geosciences
This study explores the application of hyperspectral remote sensing for mineral mapping purposes at Elephant Mountain, Interior Alaska, focusing on airborne and laboratory-based spectroscopic techniques. Hyperspectral imaging (HSI) was conducted using the HySpex imaging system, acquiring airborne hyperspectral imagery over an area of proven mineral resources. The research aimed to evaluate the effectiveness of HSI in identifying alteration minerals, considering the impact of spatial resolution, sensor altitude, and spatial resampling on mineral detection accuracy. A spectral feature-fitting algorithm within the USGS-developed PRISM software was employed to compare airborne-derived spectra with USGS spectral library standards. Laboratorybased spectrometric analyses of rock samples …
Earth Analogue Analysis Of Volcanic/Tectonic Interactions With Applications To Venusian Stresses, Michael Ortigoza
Earth Analogue Analysis Of Volcanic/Tectonic Interactions With Applications To Venusian Stresses, Michael Ortigoza
Theses and Dissertations
Venus shares many geological similarities with Earth, yet its tectonic processes and magma injection mechanisms remain poorly understood. A key question in planetary geology is how effusive volcanism persists despite the intense horizontal compression terrestrial bodies experience over time. To explore these issues, we examine the Spanish Peaks dike swarm in Colorado which serves as an ideal site for investigating magma intrusion under compressive stress conditions. Through field mapping, orientation measurements, and structural analysis, we identify a strong relationship between pre-existing joints and dike orientations, suggesting that these fractures serve as critical magma pathways in compressive regimes. Additionally, evidence of …
A Dual Perspective On Fault Mechanics: Insights From Laboratory Acoustic Emissions And Induced Seismicity, Roshan Koirala
A Dual Perspective On Fault Mechanics: Insights From Laboratory Acoustic Emissions And Induced Seismicity, Roshan Koirala
Electronic Theses and Dissertations Archive
Earthquakes occur across multiple spatial scales depending on fault zone characteristics and mechanics. Fault failure, the mechanism responsible for earthquakes, is driven by the complex interaction of stress, material properties, fault structure, and fluids. Understanding how these factors impact fault stability is key to seismic hazard assessment. Seismological observations provide crucial information about fault mechanics. However, directly measuring the influence of fault properties on earthquake nucleation and fault rupture remains a significant challenge. This dissertation investigates the multi-scale processes of earthquake nucleation and fault failure. This involves integrating high-precision locations of acoustic emission events (AEs) in laboratory fault gouge experiments …
New Petrographic And Geochemical Constraints On Pre-Eruptive Storage Conditions And Their Control On Eruptive Styles In Martinique’S Recent Volcanic Systems, Abigail Martens
USF Tampa Graduate Theses and Dissertations
This dissertation investigates the volcanic systems of Martinique Island, focusing on magma storage conditions, magmatic evolution, and eruption dynamics. Chapter 3 presents a petrographic analysis of volcanic rocks from the island’s old, intermediate, and recent arcs, examining the evolution of plagioclase textures and the increasing abundance of other mineral phases, such as pyroxene, amphibole, olivine, and quartz, which provide insights into changing magmatic conditions. The main research is divided into two projects. Chapter 4 addresses the pre-eruptive storage conditions (pressure and temperature) of magmas beneath recent (<5 Ma) volcanic complexes (Morne Jacob, Piton du Carbet, Trois Îlets, Mt. Conil, and Mt. Pelée), exploring magma evolution, crystallization, and the role of lower crustal injections and flank collapses in triggering eruptions. Results reveal variable magma storage depths (<6 km), with significant temperature and pressure variations, indicating complex magmatic systems. Chapter 5 focuses on the Roches-Genty ignimbrite in southwestern Martinique, investigating its stratigraphy, geochemistry, and age using field mapping, grain size analysis, and 40Ar/39Ar dating. The study identifies two distinct sub-Plinian eruptive phases associated with the Dizac ignimbrite, with ages of 3.37 ± 0.14 Ma and 2.10 ± 0.26 Ma, providing insights into past explosive volcanic activity. Geochemical analysis confirms an andesitic composition, similar to regional volcanic systems. This dissertation enhances understanding of Martinique’s volcanic history, providing valuable insights into magmatic processes and eruption dynamics, with implications for volcanic hazard assessments in the Lesser Antilles.
Proof Of Concept: Using Uas Technology To Accomplish Aerial Roof Inspections, Madison R. Fanning
Proof Of Concept: Using Uas Technology To Accomplish Aerial Roof Inspections, Madison R. Fanning
Theses and Dissertations
With the growing use of simulation across industries, the digital twin remains an underexplored research area, particularly in emergency management and response. Its real-time updating capability is often overlooked due to the misconception that "digital twin" is merely a complex term for simulation. This paper highlights its distinctiveness through an evasion exercise involving two independent entities in a collocated environment. Using a highly integrated virtual environment (HIVE) and internet of things (IoT) devices, we link the physical system with an analytical simulation, demonstrating the impact of lag times in high-pressure scenarios. The computational model leverages agent-based modeling (ABM) and discrete-event …
Machine Learning For Optimized Ocean Exploration Data Analysis, Puja Banerjee
Machine Learning For Optimized Ocean Exploration Data Analysis, Puja Banerjee
Open Access Dissertations
The deep sea remains one of the most crucial frontiers in Earth sciences, with vast unknowns regarding its biodiversity, ecosystem dynamics, and geological features and processes, and impact and interaction with humans. Ocean exploration seeks to address this gap by focusing data collection in some of the least known places on the planet in order to significantly expand our knowledge of marine ecosystems, geological formations, and oceanographic processes. Ocean exploration datasets provide crucial insights into a wide range of scientific domains including: deep sea biodiversity, seafloor morphology, and deep-sea soundscapes. The advent of autonomous and remotely operated underwater vehicles (AUVs …
Predicting Evapotranspiration, Quick Flow, And Recharge In The Contiguous United States Through 2100, Paige Aldenberg
Predicting Evapotranspiration, Quick Flow, And Recharge In The Contiguous United States Through 2100, Paige Aldenberg
Open Access Master's Theses
Groundwater pumping has more than doubled since 1950 across the United States and now accounts for more than 50% of water use in much of the country. These high pumping rates have exceeded recharge in many aquifers, especially in the dry Western United States. As a result, water levels are declining, increasing water scarcity for humans, and causing various adverse ecosystem impacts. So, predictions of future groundwater recharge rates, especially in the face of changing climates, are necessary for informing future water management practices. While historical groundwater recharge rates have been estimated across broad geographic regions, high-resolution predictions of future …
Analysis Of Lava Flow Paths Using Remote Sensing And Geomorphological Techniques, Oluwatosin Oluyemisi Ayo
Analysis Of Lava Flow Paths Using Remote Sensing And Geomorphological Techniques, Oluwatosin Oluyemisi Ayo
Dissertations, Master's Theses and Master's Reports
Lava flows have severe impacts on the Earth’s surface, communities, and natural habitats. Accurate modeling of lava flow paths is crucial for volcanic hazard assessment and risk mitigation. This research integrated remote sensing, geographic information systems, geomorphological techniques, and hydrologic analysis to numerically determine the optimal ground sample distance (GSD) of digital elevation models (DEMs) for delineating lava flow paths. Two volcanic regions were analyzed: the Afar Region of Ethiopia (Alu, Dalaffilla, and Erta Ale volcanoes) and the Reykjanes Peninsula of Iceland (Fagradalsfjall volcano). Forward and backward modeling methods were used to simulate potential lava flow paths. Remote sensing data, …
Fault Box Modeling Of Dip Slip Faults: A Framework For Fault Box Design And Future Studies, Hailey Pressnell
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 …
Applications Of Phosphorus Geochemistry To Utah Lake, Jacob Barry Taggart
Applications Of Phosphorus Geochemistry To Utah Lake, Jacob Barry Taggart
Theses and Dissertations
This compilation of studies provides an examination of phosphorus dynamics in the suspended solids, water column, and lakebed sediments of Utah Lake, a large, shallow, and phosphorus-rich water body. The first study introduces a novel phosphorus microfractionation (P-MF) method designed for small samples of suspended solids and sediments. This method reveals that suspended solids in Utah Lake can have a significantly higher phosphorus content across most fractions compared to lakebed sediments, highlighting the importance of considering suspended solids in nutrient management strategies. The second study analyzes historical phosphorus mass and concentrations, demonstrating that water column phosphorus levels have remained stable …
Bio-Based Polyurethane Composites Using Safflower Oil, Silicon & Phosphorus-Based Flame-Retardants, Smit Chaudhary
Bio-Based Polyurethane Composites Using Safflower Oil, Silicon & Phosphorus-Based Flame-Retardants, Smit Chaudhary
Electronic Theses & Dissertations
Polyurethane (PU) is a versatile polymer that forms when isocyanate compounds react with compounds containing hydroxyl groups, typically polyols. It can exist in various forms, including rigid foams, flexible foams, coatings, adhesives, elastomers and composites, and is known for its durability, flexibility, rigidity and resistance to abrasion, chemicals, and weathering. PU finds extensive applications in industries ranging from construction and automotive to furniture and footwear. When it comes to vegetable oil-based PU composites, derived from renewable resources, offer eco-friendly alternatives in industries seeking sustainable materials. These composites demonstrate promise in applications for enhanced mechanical properties. This work investigates the PU …
Chemical Recycling Of Bio-Based Polyurethane Foams: Evaluating Bio-Based Glycols In Comparison To Petroleum-Based Glycols, Anirudh Thorbole Mr.
Chemical Recycling Of Bio-Based Polyurethane Foams: Evaluating Bio-Based Glycols In Comparison To Petroleum-Based Glycols, Anirudh Thorbole Mr.
Electronic Theses & Dissertations
The paradigm shift towards bio-based polyurethane foams (bio-PUF) has significantly increased post-consumer waste. To address this issue, this research represents a novel approach to enhance sustainable development in the recycling industry by replacing traditional petroleum-based glycols with sustainable bio-based alternatives. This study explores the glycolysis of bio-PUF using bio-based SG-522 glycol and polyethylene glycol (PEG) for comparison. The findings from this research as outlined, reveal no significant differences in depolymerization time between the two glycols, achieving proper depolymerization and high recovery yields of over 95% after solvent purification. Comprehensive FT-IR and NMR analyses confirmed the successful degradation of bio-PUF and …
Castor Oil-Based Polyurethane Adhesives: Effect Of Cross-Linker On The Bond Strength, Mayankkumar Chaudhary
Castor Oil-Based Polyurethane Adhesives: Effect Of Cross-Linker On The Bond Strength, Mayankkumar Chaudhary
Electronic Theses & Dissertations
Adhesives are important for binding diverse materials, promoting structural integrity and functional versatility in countless daily life applications. An enormous obstacle remains in the development of polyurethane (PU) adhesives exhibiting excellent bonding strength. Designing a chain extender with appropriate molecular structures is critical to improving the bonding strength of PU-based adhesives. In this work, PU-based adhesive was prepared using castor-oil-based polyol (COP) and diisocyanate. The bonding strength of the adhesive was improved by adding chain extenders such as N, N-bis(2-hydroxyethyl) thiophene-2,5-dicarboxamide (ETP) and N, N-Bis(2-hydroxyethyl)-terephthalamide (ETAM). The modified adhesive showed high bonding strength after the addition of chain extenders due …
Predicting Ph At In-Situ Temperature For Aquatic Environments, Sarah E. Bartoloni
Predicting Ph At In-Situ Temperature For Aquatic Environments, Sarah E. Bartoloni
USF Tampa Graduate Theses and Dissertations
pH is typically measured at a constant temperature and, as needed, converted to in-situ temperature using a system of thermodynamic equations. Using this equilibrium approach, adjustment of pH to in situ conditions requires two measured CO2 system parameters (pH, total alkalinity, dissolved inorganic carbon, or CO2 fugacity). Currently, when pH is the only measured CO2 system parameter, linear models are used to adjust the pH to in-situ temperature. Although many studies have attempted to optimize CO2 equilibrium constants (K1 and K2) for the CO2 system over a range of conditions, very little prior work has experimentally examined which CO2 system …
The Revitalization Of Lalibela’S Heritage Site Through The Establishment Of A New Visitor Center, Endale Tesfay
The Revitalization Of Lalibela’S Heritage Site Through The Establishment Of A New Visitor Center, Endale Tesfay
Bachelor of Architecture Theses - 5th Year
ABSTRACT
Revitalizing the heritage site of the rock-hewn church of Lalibela is counted as revitalizing a city because the site is the biggest heritage site. It is found in the Amhara region of north Ethiopia, and the properties were inscribed on the World Heritage List in 1978. Eleven churches were found at the site, and all of them were carved out of the living rock in the 12th century, not constructed traditionally. The churches are grouped into three and connected by a walking trail, tunnel, and trench. Groups of churches have interior and exterior spaces, and their floors, roofs, walls, …
Geologic Face Mapping Methodology Utilizing Global Positioning Systems And Unmanned Aircraft Systems, Luke Whitenburg
Geologic Face Mapping Methodology Utilizing Global Positioning Systems And Unmanned Aircraft Systems, Luke Whitenburg
Electronic Theses and Dissertations
Geologic field mapping has traditionally been a low-technology process, limited by time in the field and a delicate balance between data collection and coverage area. Advancements in Global Positioning Systems (GPS), Unmanned Aircraft Systems (UAS), and software packages offer new tools and techniques for collecting high volume, accurate geologic information. These tools can provide geologists with safe and efficient ways to collect and process greater volumes of field data.
Field data for this study was collected from three open pit mines using a Trimble Geo 7X GPS unit with Geo 7 Series Rangefinder module and a Phantom 4 Pro V2.0 …
Estimating Crustal Thickness In Northwest Louisiana Using The Receiver Function Method, Delton Samuel
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 …
Time And Space Evolution Of Late Permian To Early Triassic Deposits In The Northern Delaware Basin, Southeast New Mexico, U.S.A.: Sediment Sources, Dispersal Pathways, And Timing Of Salt Deformation, Omonde Sitou Akakpo
Electronic Theses and Dissertations
The northern Delaware Basin in southeast New Mexico recorded the deposition of thick evaporite beds followed by siliciclastic materials between the late Permian and Early Triassic. Mineralogy and whole-rock geochemistry of the bioturbated zone and the first mudstone/halite (M1/H1) informal units in the Los Medaños Member (Rustler Formation) suggest felsic volcanic arc origins for the bioturbated zone and felsic upper continental crust passive margin origins for the M1/H1. The previously studied marine transgression that deposited the bioturbated zone likely transported detritus from southern North America and Central American volcanic arcs into the northern Delaware Basin, whereas the regression allowed migration …