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Tectonomagmatic Evolution Of Northwestern Mexico, And Applications Of Machine Learning In Economic Geology, Jose Antonio Garcia 2021 University of Texas at El Paso

Tectonomagmatic Evolution Of Northwestern Mexico, And Applications Of Machine Learning In Economic Geology, Jose Antonio Garcia

Open Access Theses & Dissertations

The work presented here was conducted in two study areas: La Preciosa mining project (Chapters 1 and 2) and Ray Mine (Chapter 3). Chapter 1 of this dissertation contributes to the tectonomagmatic evolution of northwestern Mexico by focusing on the temporal changes in magma source(s) regions, magma generation processes, and tectonic implications. In this chapter, I provide thin section analyses, whole rock geochemistry, in-situ zircon U-Pb ages and Hf isotope compositions of subsurface lithologies from La Preciosa mining project; located in the northwestern corner of Mesa Central, Durango, Mexico. The newly acquired data identified five magmatic events. The first consists …


Structural And Stratigraphic History Of A Deformed Diapir Margin, Onion Creek Salt Diapir, Paradox Basin, Utah, David Lankford-Bravo 2021 University of Texas at El Paso

Structural And Stratigraphic History Of A Deformed Diapir Margin, Onion Creek Salt Diapir, Paradox Basin, Utah, David Lankford-Bravo

Open Access Theses & Dissertations

The Onion Creek Salt Diapir (OCSD) located in the northern Paradox Basin in Utah is a 0.6 km wide X 3.6 km long X 1.6 km tall salt diapir surrounded by variably deformed Paleozoic through Cenozoic strata. The area is a classic area for the study of deformation around salt diapirs. This study uses high-resolution GPS-enabled-tablet and 3D photogrammetric outcrop model-based field mapping, section measuring, thin section petrography, structural restorations, and newly developed 3D modelling workflows to document the styles, timing, nature, and distribution of deformation in strata surrounding the OCSD. Permian Cutler Group sediments on the northern margin of …


A 60- Year Record Of The Demotechnic Index Of States, 1960-2019, Gavin James Kellough 2021 University of Arkansas, Fayetteville

A 60- Year Record Of The Demotechnic Index Of States, 1960-2019, Gavin James Kellough

Graduate Theses and Dissertations

A country’s dependency on energy resources can be interpreted through the calculation of energy indices. The Demotechnic Index (DI) was used to determine the trajectory of energy efficiency of each state in the United States over the period 1960-2019. The DI serves as a measure of the energy intensity of states and a proxy for energy sustainability of each state.The DI is the ratio of total energy use to total metabolic energy demand of a population. Mathematically, DI = (E_T-E_M)/E_M E_T represents the total energy used (metabolic energy + technological energy in kilojoules annually, kJ/y), while EM represents the basic …


Detrital Zircon U-Pb Geochronology Of Upper Mississippian Siltstone, Oklahoma And Arkansas, Linnea Johnson 2021 University of Arkansas, Fayetteville

Detrital Zircon U-Pb Geochronology Of Upper Mississippian Siltstone, Oklahoma And Arkansas, Linnea Johnson

Graduate Theses and Dissertations

Although Upper Mississippian strata have been characterized extensively using lithostratigraphy, sequence stratigraphy, and biostratigraphy across the North American midcontinent, the origin of the silt comprising the Meramec STACK (Sooner Trend Anadarko Basin, Canadian and Kingfisher counties) reservoirs of the Anadarko Basin in west-central Oklahoma and age equivalent units is not well understood, despite its economic importance as an unconventional petroleum reservoir. Previously published models have variously invoked fluvial, marine, and aeolian sediment transport for Upper Mississippian siltstone present along the paleo-shelf edge of the Laurentian craton. This study uses detrital zircon U-Pb geochronology and grain morphology, handheld x-ray fluorescence (hXRF) …


Machine Learning Applied To A Modern-Pleistocene Petrographic Dataset: The Global Prediction Of Sand Mineralogy (Gloprsm) Model, Isaac Johnson 2021 University of Arkansas, Fayetteville

Machine Learning Applied To A Modern-Pleistocene Petrographic Dataset: The Global Prediction Of Sand Mineralogy (Gloprsm) Model, Isaac Johnson

Graduate Theses and Dissertations

Petrography has long been used as a tool to decipher the sedimentary provenance of sand and sandstone from the relative proportions of framework grain types. Petrographers have also related the proportions of quartz (Q), feldspar (F), and lithic (L) grains to the processes that form and modify sediments within sediment routing systems. This past work has shown that factors including source lithology, climate, transport history, and tectonism work in concert to modify the framework mineralogy of sand. However, there is a lack of a quantitative understanding of the interactions and feedbacks between these factors and how they modify sand mineralogy. …


The Morphodynamic Interaction Of River Deltas And Their Marshes, Kelly M. Sanks 2021 University of Arkansas, Fayetteville

The Morphodynamic Interaction Of River Deltas And Their Marshes, Kelly M. Sanks

Graduate Theses and Dissertations

Globally, many of the largest river deltas contain vast marsh platforms that are currently threatened due to a combination of anthropogenic alterations to rivers and increasing relative sea level rise. Restoration and management plans for river deltas depend on optimizing riverine sediment accumulation in marsh platforms. However, the accumulation of organic material in marsh platforms is often neglected in predictive models and the interaction of ecogeomorphic processes governing marsh accumulation with the physical processes governing river delta growth is poorly understood.

Herein, I investigate this complex relationship through a combination of field and experimental studies. I show that in coastal …


Global Analysis Of The Hydrologic Sensitivity To Climate Variability, Marisol Dominguez 2021 University of Texas at El Paso

Global Analysis Of The Hydrologic Sensitivity To Climate Variability, Marisol Dominguez

Open Access Theses & Dissertations

Identifying the regions with greatest changes in their hydrologic behavior under extreme weather events in the 21st century, constitutes a study priority of global impact. Here, we present a global assessment assessing the sensitivity of the world’s water landscapes to climate variability during 2001-2016, using a new metric called the Hydrologic Sensitivity Index (HSi). This equation is based on the well-known Budyko curve that uses annual values of Potential and Actual Evapotranspiration (PET and AET), and Precipitation (P), to assess the hydrologic behavior of a location under a given climatic condition by plotting the Evaporative Index (AET/P) against the Dryness …


Fine Grained Delta Front Sediment Transport, Sarah Noel 2021 University of New Orleans, New Orleans

Fine Grained Delta Front Sediment Transport, Sarah Noel

LSU New Orleans Theses and Dissertations

Insights into transformative coastal processes are unlocked though understanding sediment transport mechanisms in fine-grained delta front environments. Movement of fine-grained sediments on delta fronts is not wholly explained through advection settling models. While advection settling models generally assume deposition into a still body, numerical modeling of sediment re-entrainment suggests there may be tidal, wave, and/or non-steady hydrograph influences allowing particles to reach greater distances by altering the decelerating velocity field. This research explores both an advection settling model and a mass conservation Rouse profile model to understand the irreducible delta front processes controlling sediment deposition. Using field data collected on …


Pcor Partnership Atlas, Wesley D. Peck, Earl P. Battle, Kari Suedel, Kyle A. Glazewski, Kevin C. Connors, James A. Sorensen, John A. Hamling, Charles D. Gorecki, Edward N. Steadman, John A. Harju 2021 University of North Dakota. Energy and Environmental Research Center

Pcor Partnership Atlas, Wesley D. Peck, Earl P. Battle, Kari Suedel, Kyle A. Glazewski, Kevin C. Connors, James A. Sorensen, John A. Hamling, Charles D. Gorecki, Edward N. Steadman, John A. Harju

EERC Maps and Infographics

The Plains CO2 Reduction (PCOR) Partnership Atlas provides a regional profile of CO2 sources and potential storage locations across the PCOR Partnership region. The sixth edition provides an up-to-date look at PCOR Partnership initiative activities, including additional regional characterization and updates on commercial projects. Additional background information on carbon capture, utilization, and storage (CCUS) is included to give a better understanding of how CCUS addresses concerns about climate change while allowing future energy needs to be met.


Chronostratigrapy Of Miocene Fluviolacustrine Deposits In Amargosa Valley, Levente Laisz 2021 Loma Linda University

Chronostratigrapy Of Miocene Fluviolacustrine Deposits In Amargosa Valley, Levente Laisz

Loma Linda University Electronic Theses, Dissertations & Projects

Fluviolacustrine deposits of middle Miocene age occur on the western margins of the Amargosa Valley, in the central Basin and Range. These deposits contain the earliest pupfish (Cyprinodon) reported from the fossil record. National Park collections contain specimens of pupfish fossils, interpreted as possibly Pliocene; however the exact collection location and stratigraphic horizon was not known. Therefore, the geographic extent of the fossil locality and geologic age of these specimens were uncertain. Recently, these collection sites were relocated and additional sites were discovered. Ar-Ar dating of interbedded tuffs established the first appearance datum of pupfish at 14.79 Ma and extended …


Sedimentary Dna And Molecular Evidence For Early Human Occupation Of The Faroe Islands, Lorelei Curtin, William J. D’Andrea, Nicholas L. Balascio, Sabrina Shirazi, Beth Shapiro, Gregory A. de Wet, Raymond S. Bradley, Jostein Bakke 2021 Lamont-Doherty Earth Observatory

Sedimentary Dna And Molecular Evidence For Early Human Occupation Of The Faroe Islands, Lorelei Curtin, William J. D’Andrea, Nicholas L. Balascio, Sabrina Shirazi, Beth Shapiro, Gregory A. De Wet, Raymond S. Bradley, Jostein Bakke

Geosciences: Faculty Publications

The Faroe Islands, a North Atlantic archipelago between Norway and Iceland, were settled by Viking explorers in the mid-9th century CE. However, several indirect lines of evidence suggest earlier occupation of the Faroes by people from the British Isles. Here, we present sedimentary ancient DNA and molecular fecal biomarker evidence from a lake sediment core proximal to a prominent archaeological site in the Faroe Islands to establish the earliest date for the arrival of people in the watershed. Our results reveal an increase in fecal biomarker concentrations and the first appearance of sheep DNA at 500 CE (95% confidence interval …


Analysis Of Titan's Fluvial Features Using Numerical Modeling, Jeshurun Horton 2021 University of Arkansas, Fayetteville

Analysis Of Titan's Fluvial Features Using Numerical Modeling, Jeshurun Horton

Mechanical Engineering Undergraduate Honors Theses

River channels have been observed near the Huygens probe landing site on the surface of Titan, along with evidence of rounded water ice boulders transported through fluid flow. Evidence near the landing site suggests active flow of liquid methane, which has motivated the study of the effects of sediment load and channel sizes on Titan’s fluvial features. A numerical model is used to determine the viscosity, flow velocity, and critical boulder transport diameter based on channel size, slope, and a range of sediment concentrations. This model achieves two ends: first, observed boulder diameters are used to determine the ideal channel …


Understanding The Multiple Small Magnitude Induced Seismic Soil Fatigue Potential On Hazard Assessments, Merissa L. Zuzulock, Oliver Denzil S. Taylor, Norbert H. Maerz 2021 Missouri University of Science and Technology

Understanding The Multiple Small Magnitude Induced Seismic Soil Fatigue Potential On Hazard Assessments, Merissa L. Zuzulock, Oliver Denzil S. Taylor, Norbert H. Maerz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Soils under spacio-temporally clustered events loading are susceptible to soil fatigue as pore pressure dissipates and the soil is unable to recover. This potential for damage from soil fatigue is identified through an induced seismic fatigue equation provided in this paper. The objective of this paper is to present an induced seimic equation for soils under spacio-temporally clustered impulse loading to identify potential hazards to the subsurface that supports critical infrastructure. It further illustrates the use of the equation as determined from a comparison of three varying soil profiles with resulting data that shows a need to establish new critieria …


Factors Controlling Longshore Variations Of Beach Changes Induced By Hurricane Hermine Along Pinellas County Beaches, West-Central Florida, Wenhan Zhai 2021 University of South Florida

Factors Controlling Longshore Variations Of Beach Changes Induced By Hurricane Hermine Along Pinellas County Beaches, West-Central Florida, Wenhan Zhai

USF Tampa Graduate Theses and Dissertations

Hurricane Hermine, 2016, impacted the coast of west-central Florida and generated high waves superimposed on elevated wave levels which caused significant beach erosion. A total of 122 profiles, spaced about 300 m apart, were surveyed 2 weeks before and one week after the storm to examine the beach changes along three barrier islands along the coast of west-central Florida. including Sand Key, Treasure Island and Long Key. In order to investigates the longshore variations of beach/nearshore changes induced by storm, several parameters were defined and calculated including beach volume changes, berm height, beach width, foreshore slope, as well as sandbar …


Lithological And Geochemical Characterization Of Ramp Sediments And A Depositional Model Of The Ordovicain Garden City Formation, Northeastern Utah, Kenneth W. Kehoe 2021 Utah State University

Lithological And Geochemical Characterization Of Ramp Sediments And A Depositional Model Of The Ordovicain Garden City Formation, Northeastern Utah, Kenneth W. Kehoe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Ordovician Garden City Formation is a mostly marine limestone rock formation deposited in what is known today as the Northern Utah Basin in North America ~485.5 million years ago. Previous research on the Pogonip Group, a time equivalent rock formation located in the Ibex Basin south of the Northern Utah Basin, has identified nine cycles of sea-level fall and rise. However, these nine sea-level cycles have proven difficult to identify within the Garden City Formation due to the limited contrast between rock types within the rock formation. Previous research on the Garden City has approximated these sea-level cycles through …


Speleogenesis In A Lens Of Metamorphosed Limestone And Ankerite: Ochtiná Aragonite Cave, Slovakia, Pavel Bella, Pavel Bosák, Petr Pruner, Helena Hercman, Katarína Pukanská, Karol Bartoš, Ľudovít Gaál, Dagmar Haviarová, Peter Tomčík, Šimon Kdýr 2021 Slovak Caves Administration, Liptovský Mikuláš, Slovakia

Speleogenesis In A Lens Of Metamorphosed Limestone And Ankerite: Ochtiná Aragonite Cave, Slovakia, Pavel Bella, Pavel Bosák, Petr Pruner, Helena Hercman, Katarína Pukanská, Karol Bartoš, Ľudovít Gaál, Dagmar Haviarová, Peter Tomčík, Šimon Kdýr

International Journal of Speleology

The Ochtiná Aragonite Cave (Western Carpathians) represents an unique natural phenomenon. It originated under particular lithological and hydrogeological conditions of the Ochtiná Karst in which several isolated lenses of Paleozoic crystalline limestone (marbles), partly metasomatically altered to ankerite, are enclosed by phyllites. Meteoric water seepage through non-carbonate rocks dissolved limestone and caused the oxidation of ankerite to Fe oxyhydroxides. Carbon dioxide produced during ankerite oxidation enhanced limestone dissolution. The maze cave consists of parallel fault-controlled linear passages and chambers interconnected by transverse horizontal passages. Phreatic and epiphreatic solution morphologies resulted from slowly moving or standing water. These include flat ceilings …


Community College Geoscience Faculty Perspectives On Critical Thinking Instructional Tools, Mariela Salas Bao 2021 Portland State University

Community College Geoscience Faculty Perspectives On Critical Thinking Instructional Tools, Mariela Salas Bao

Dissertations and Theses

Research has shown that modern courses and programs designed to foster critical thinking vary in both content and delivery, in turn leading to differences in their effectiveness. Few studies have investigated critical thinking among nontraditional students at community colleges taking STEM courses, especially within the geosciences. Furthermore, such research has focused primarily on the students with few if any studies involving faculty. This study examined the perceptions held by community college geoscience faculty regarding critical thinking and how such perceptions influenced their choice of instructional strategies. This study used a basic qualitative methodology and a maximum variation sampling to select …


A New Phosphatized Ophiuroid From The Lower Triassic Of Nevada And Its Position In The Evolutionary History Of The Ophiuroidea (Echinodermata), Ben Thuy, Vivienne Maxwell, Sara B. Pruss 2021 Natural History Museum Luxembourg

A New Phosphatized Ophiuroid From The Lower Triassic Of Nevada And Its Position In The Evolutionary History Of The Ophiuroidea (Echinodermata), Ben Thuy, Vivienne Maxwell, Sara B. Pruss

Geosciences: Faculty Publications

The Lower Triassic fossil record of brittle stars is relatively rich, yet most records published to date are based on poorly preserved or insufficiently known fossils. This hampers exhaustive morphological analyses, comparison with recent relatives or inclusion of Early Triassic ophiuroid taxa in phylogenetic estimates. Here, we describe a new ophiuroid from the Lower Triassic of Nevada, preserved as phosphatized skeletal parts and assigned to the new taxon Ophiosuperstes praeparvus gen. et sp. nov Maxwell, V. Pruss. S.B. This unusual preservation of the fossils allowed for acid-extraction of an entire suite of dissociated skeletal parts, including lateral arm plates, ventral …


Revisiting The Cretaceous-Paleogene Boundary In Western Kentucky, Usa, Jarred Asselta 2021 Murray State University

Revisiting The Cretaceous-Paleogene Boundary In Western Kentucky, Usa, Jarred Asselta

Scholars Week

This study revisits a Cretaceous-Paleogene (K-Pg) sedimentary section in western Kentucky to determine the nature of this boundary and the depositional environments. Although previous pollen work identified the boundary over four decades ago, to our knowledge no work has been carried out at this important K-Pg boundary site. A combination of stratigraphy and sedimentology were used to characterize the section in detail. Bulk and oriented samples were collected for grain-size, geochemical, and petrographic analysis. We relocated the site and measured 1.5m of section that includes the K-Pg boundary. Four distinct units were identified and from base to top of section …


Detailed Structural And Stratigraphic Analysis Of The Salt-Sediment Interactions On Top Of The Wheeler Dome Salt Tongue, Mississippi Canyon Area, Gulf Of Mexico, Ryan Jaska 2021 Stephen F. Austin State University

Detailed Structural And Stratigraphic Analysis Of The Salt-Sediment Interactions On Top Of The Wheeler Dome Salt Tongue, Mississippi Canyon Area, Gulf Of Mexico, Ryan Jaska

Electronic Theses and Dissertations

The Mississippi Canyon is in the northeastern part of the Gulf of Mexico, south of the state of Mississippi. In this area, there are many different salt structures present including salt canopies, diapirs, and salt pillows. The Callovian aged Louann Salt covers this area and is the cause of many of the salt structures and structures of the overlying formations seen in Gulf of Mexico today. Salt is mobile when subjected to stress from overlying sediment and gravity. Stress will force the salt to not only move upward, but to also move down slope deeper into adjacent basins through the …


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