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Investigation Of Residual Mineral Content Of Bauxite Stockpiles, Saline Mining District, Arkansas, U.S.A., Melanie L. Ertons 2024 Stephen F Austin State University

Investigation Of Residual Mineral Content Of Bauxite Stockpiles, Saline Mining District, Arkansas, U.S.A., Melanie L. Ertons

Electronic Theses and Dissertations

The former mining town of Bauxite is in the Saline County Mining District, in central Arkansas. Bauxite is located approximately 40 km (25 mi) southwest of Little Rock just east of Benton, Arkansas. This area contains extensive deposits of bauxite ore and nepheline syenite previously mined by Aluminum Company of America using open pit and subsurface mining techniques. This study incorporates five bauxite stockpiles (SP1, Clay, SP2, SP3, SP4) with varying amounts of alumina content situated on approximately 10 acres of land within an area of the former mine recognized as Section 20. Over the past several years, there has …


Unboxing The Complicated Near Term Climatic And Geomorphic History Of Mars, Joshua Matthew Williams 2024 University of New Mexico - Main Campus

Unboxing The Complicated Near Term Climatic And Geomorphic History Of Mars, Joshua Matthew Williams

Earth and Planetary Sciences ETDs

It has long been thought that glacial processes were unlikely within the tropical regions of Mars. However, growing evidence, including this work has identified and quantified relic glacial forms within the equatorial regions. These findings have major implications for understanding Martian climate history and its sensitivity to changes in insolation. As well, the presence of ice in the equatorial region of Mars has significant implications for the past global redistribution of the water ice in the Martian cryosphere. In this manuscript, I clarify and refine our understanding of the morphology of glacial features in the equatorial zone by applying novel …


Paleoecology Of The Late Cretaceous Western Interior Seaway And Gulf Coastal Plain, Ceara Kathleen Quinn Purcell 2024 University of New Mexico

Paleoecology Of The Late Cretaceous Western Interior Seaway And Gulf Coastal Plain, Ceara Kathleen Quinn Purcell

Earth and Planetary Sciences ETDs

This dissertation presents research into the paleobiogeography and paleoecology of the Western Interior Seaway (WIS) and Gulf Coastal Plain (GCP) during the Late Cretaceous. The dataset utilized here includes an extensive record of marine invertebrates from over 200 years of fossil collecting and sedimentary data collated from over 45 different literature sources, representing approximately 17 million years of deposition. The high-resolution of this dataset, and its extensive geographic distribution and temporal duration, make it ideal for exploring various ecological questions. Using these data, I have attempted to reconstruct paleobiogeographic provinces as published in prior works, explore functional diversity patterns, and …


The Geology And Geochemistry Of The Western Iron Ore Group Greenstone Belt, Singhbhum Craton, Eastern India, JORDAN WRIGHT 2024 Southern Methodist University

The Geology And Geochemistry Of The Western Iron Ore Group Greenstone Belt, Singhbhum Craton, Eastern India, Jordan Wright

Earth Sciences Theses and Dissertations

This thesis presents new data on the origin of the Western Iron Ore Group (W-IOG), a Paleoarchean succession deposited on sialic rocks of the Singhbhum Craton. U-Pb ages from zircons from a tuff overlying the Lower Shales just below a banded iron formation (BIF) pin the age of the section to 3.39 Ga. Unconformably overlying the whole IOG section is the Darjing Group, which contains the Birtola Sandstone (on the basis of this work, now estimated to be 2.35 Ga). The lack of penetrative deformation and low-grade metamorphism makes these rocks excellent subjects for combined radiogenic and stable isotope studies. …


Textural Investigation Into Rapid Welding Transitions In The Tuff Of Leslie Gulch Along Succor Creek At The Mahogany Mountain-Three Fingers Rhyolite Field, Southeastern Oregon, Alicia J. Martinez-Garling, Martin J. Streck 2024 Portland State University

Textural Investigation Into Rapid Welding Transitions In The Tuff Of Leslie Gulch Along Succor Creek At The Mahogany Mountain-Three Fingers Rhyolite Field, Southeastern Oregon, Alicia J. Martinez-Garling, Martin J. Streck

Student Research Symposium

The Mahogany Mountain-Three Fingers Rhyolite Field (MM-TFrf) in southeastern Oregon, associated with mid-Miocene rhyolite activity and Columbia River flood basalts, has been the subject of geological scrutiny. Previous studies proposed separate origins for the tuff of Leslie Gulch (LGT) and Spring Creek, but Benson and Mahood (2006) suggested a single ignimbrite event at 15.8 Ma, prompting a reassessment of MM-TFrf's history. This research focuses on LGT, investigating textural disparities between welded and non-welded tuff formations. Petrographic examinations delve into the transformation stages of pyroclastic tuff deposition, revealing the dynamic influences of volcanological and magmatic processes on welded and non-welded tuff …


Analyzing Intensifying Storm Events Correlation To Landslide Frequency In Portland’S West Hills, Aurora Villa Juan 2024 Portland State University

Analyzing Intensifying Storm Events Correlation To Landslide Frequency In Portland’S West Hills, Aurora Villa Juan

Student Research Symposium

As the Pacific Northwest climate changes, extreme weather, such as intensifying storms, and a shift in the type of precipitation experienced with warmer winters causing more precipitation to fall as rain instead of snow, may lead to an increased frequency of landslides. There have been several recent landslides in Portland, noticeable to the public, particularly in areas of high elevation such as Council Crest, which stands at 1,073 feet. Additionally, residents of neighboring homes have observed changes in the landscape, including those on private properties. To better safeguard both public and private property, comprehensive research and mitigation efforts are required. …


Controls On Soft Tissue And Cellular Preservation In Late Eocene And Oligocene Vertebrate Fossils From The White River And Arikaree Groups Of Nebraska, South Dakota, And Wyoming, John E. Gallucci, Grace Woolslayer, Kelsey Barker, Brian Kibelstis, Allison R Tumarkin-Deratzian, Paul V. Ullmann, David E. Grandstaff, Dennis O. Terry 2024 Rowan University

Controls On Soft Tissue And Cellular Preservation In Late Eocene And Oligocene Vertebrate Fossils From The White River And Arikaree Groups Of Nebraska, South Dakota, And Wyoming, John E. Gallucci, Grace Woolslayer, Kelsey Barker, Brian Kibelstis, Allison R Tumarkin-Deratzian, Paul V. Ullmann, David E. Grandstaff, Dennis O. Terry

School of Earth & Environment Departmental Research

Previous studies on microtaphonomy have identified multiple types of organic microstructures in fossil vertebrates from a variety of time periods and past environmental settings. This study investigates potential taphonomic, paleoenvironmental, and paleoclimatic controls on soft tissue and cellular preservation in fossil bone. To this end, fifteen vertebrate fossils were studied: eight fossils collected from the Oligocene Sharps Formation of the Arikaree Group in Badlands National Park, South Dakota, and seven fossils from formations in the underlying White River Group, including the Oligocene Brule Formation of Badlands National Park, and the Eocene Chadron Formation of Flagstaff Rim, Wyoming; Toadstool Geologic Park, …


Characterizing The Engineering Properties Of Three Lithologies From Montana And Idaho Using Acoustic Emissions And Stress-Strain Measurements, Mary Humphreys 2024 Montana Technological University

Characterizing The Engineering Properties Of Three Lithologies From Montana And Idaho Using Acoustic Emissions And Stress-Strain Measurements, Mary Humphreys

Graduate Theses & Non-Theses

In this study, stress and strain measurements from unconfined compression tests were used to determine the peak stress, yield stress, Young’s modulus, and Poisson’s ratio of 20 specimens representing three lithologies (sandstone, norite, and argillite-quartzite mix) from Idaho and Montana. Along with traditional strength and deformation parameters, crack initiation (CI) and crack damage (CD) values were also interpreted, corresponding to the stress levels associated with the formation and coalescence of microcracks as a specimen is exposed to increasing stress levels. Acoustic emissions (AE) data were collected along with traditional stress-strain data as this has become a popular method for interpreting …


Characterizing Potentially Harmful Environmental Legacy Issues Within A Declining Midwest City: A Street Sediment Study Of Northeastern Terre Haute, Indiana, Katelyn Adams '24, Ken Brown 2024 DePauw University

Characterizing Potentially Harmful Environmental Legacy Issues Within A Declining Midwest City: A Street Sediment Study Of Northeastern Terre Haute, Indiana, Katelyn Adams '24, Ken Brown

Senior Scholarly and Creative Symposium

Urban settings face unprecedented environmental challenges that include legacy issues as well as emerging pollution problems (e.g., micro-plastics) that continually impact the public health of its communities. Determining the baseline abundances of potentially harmful contaminants in soil, sediment, air, and water is essential to protecting residents. This study examines anthropogenic pollution in street sediments collected from three neighborhoods located in northeast Terre Haute, Indiana. Using stereomicroscopy, SEM/EDS, pXRF analyses, and geospatial analysis (GIS), the goal of this work is to characterize the types of pollutants present and place important constraints on their potential sources.

Stereomicroscopy on nine street sediment samples …


Dating The Ste. Genevieve Limestone In West-Central Indiana Using Sr-Isotope Stratigraphy, Claire Wolfe '24 2024 DePauw University

Dating The Ste. Genevieve Limestone In West-Central Indiana Using Sr-Isotope Stratigraphy, Claire Wolfe '24

Senior Scholarly and Creative Symposium

A section of Mississippian limestone is exposed in quarry walls at the DePauw Nature Park in Greencastle, Indiana, but its precise age is not known. This research project aimed to date the exposed wall using 87Sr/86Sr isotopic ratios to determine the absolute age. Ten samples of brachiopods and ooids were collected at various levels along the stratigraphic column. Isotope ratios were measured in these samples at ALS Scandinavia using a Neptune Plus MC-ICP-MS. Those ratios were then placed on a LOESS seawater Sr-isotope curve (McArthur, 2020) to determine the absolute age range for each sample. Whereas several samples were contaminated …


The Olmsted Fault, Southernmost Illinois: A Key To Understanding Seismic Hazard In The Northern New Madrid Seismic Zone, Christopher E. Bexfield 2024 Brigham Young University

The Olmsted Fault, Southernmost Illinois: A Key To Understanding Seismic Hazard In The Northern New Madrid Seismic Zone, Christopher E. Bexfield

Theses and Dissertations

The northernmost extent of the New Madrid seismic zone in the central USA has been investigated using an integrated approach involving both compressional-wave (P) and horizontally polarized-wave (SH) seismic reflection and regional and dedicated borehole geophysical information in order to assess seismic hazard and risk. Our study area, centered around southernmost Illinois and western Kentucky, USA, represents an area of concentrated facilities (e.g., lock and dam sites and chemical plants on the Ohio River near its confluence with the Mississippi River) as well as an area of high potential soil amplification due to earthquake shaking. Integrated high-resolution seismic reflection profiles …


The Effects Of Amphibole- And Sulfide-Producing Melts On Crustal Strength In Gabbros Of Lower Oceanic Crust In Oceanic Core Complexes, Mid-Atlantic And Southwest Indian Ridges, Trevor Hoffmann 2024 The University of Southern Mississippi

The Effects Of Amphibole- And Sulfide-Producing Melts On Crustal Strength In Gabbros Of Lower Oceanic Crust In Oceanic Core Complexes, Mid-Atlantic And Southwest Indian Ridges, Trevor Hoffmann

Master's Theses

This study investigates gabbro-cored oceanic core complexes in the slow-spreading Mid-Atlantic Ridge (MAR) and the ultraslow spreading Southwest Indian Ridge (SWIR). Dikelets are a texture found in thin section samples from these systems that form as a result of crystal-plastic deformation. Thin section samples from the Atlantis Massif, MARK Area, and 13˚-15˚ North of the MAR and the Atlantis Bank of the SWIR were observed with petrography to find these dikelets and identify what type of dikelet is present. SEM-EDS is used to identify the mineral assemblages present in the dikelets. LA-ICP-MS is used on amphibole to determine if its …


Depositional Facies And Petrophysical Characterization Of The Leonardian Carbonate (Lower Clear Fork), Tex-Mex, S.E. Field, Central Basin Platform, West Texas, Seyram Nyamasekpor 2024 Stephen F. Austin State University

Depositional Facies And Petrophysical Characterization Of The Leonardian Carbonate (Lower Clear Fork), Tex-Mex, S.E. Field, Central Basin Platform, West Texas, Seyram Nyamasekpor

Electronic Theses and Dissertations

The Lower Clear Fork from Tex-Mex, S.E. Field on the Central Basin Platform is a typical complex reservoir that displays high heterogeneity in lithological and petrophysical properties. The unit represents a producing reservoir succession of Leonardian platform carbonates deposited in shallow marine water during the Early Permian. The sediment of the Lower Clear Fork is composed of a mixed succession of dolomite interbedded with anhydrite, minor clay minerals, and siliciclastics. The high heterolithic nature of the reservoir makes efficient recovery of hydrocarbons difficult. This situation requires an understanding of the variability in depositional facies in terms of mineralogy, depositional textures …


Geologic Face Mapping Methodology Utilizing Global Positioning Systems And Unmanned Aircraft Systems, Luke Whitenburg 2024 Stephen F Austin State University

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 …


Investigating Changes In Surface Water Chemistry Across The Llano Uplift And The Balcones Fault Zone In Central Texas Using Strontium And Uranium Isotopes, Hao Tuan Pham 2024 University of Texas at El Paso

Investigating Changes In Surface Water Chemistry Across The Llano Uplift And The Balcones Fault Zone In Central Texas Using Strontium And Uranium Isotopes, Hao Tuan Pham

Open Access Theses & Dissertations

The landscape of central Texas is shaped by over one billion years of Earth's history. An array of lithology lies within central Texas along with two large geological structures. The Llano Uplift, characterized by Proterozoic metamorphic and igneous rocks dating back to 1.37 billion years ago, is encircled by Paleozoic and Mesozoic sedimentary rocks. To the southeast of the Llano Uplift lies the Balcones Fault Zone (BFZ), an extensional structural system of mostly normal faults that delineates the transition between Paleozoic-Mesozoic sedimentary rocks and Cenozoic sedimentary cover, which are influential to the regional hydrogeology. This study investigates the hydrogeological dynamics …


The Use Of Laja In Construction In Ancient Mesoamerica: A View From The Southern Gulf Lowlands Of Veracruz, Mexico, Lauren Smith 2024 Murray State University

The Use Of Laja In Construction In Ancient Mesoamerica: A View From The Southern Gulf Lowlands Of Veracruz, Mexico, Lauren Smith

Honors College Theses

The archaeology of the southern Gulf lowlands of Veracruz, Mexico is notable for its research pertaining to the Olmec culture (Jaime-Riveron 2016; Loughlin 2012; Pool 2006). The region was home to the Colossal Olmec Heads: large, easily identifiable sculptures crafted from the volcanic rock of the Tuxtlas Volcanic Field. The use of volcanic resources in such grand presentations may instill a bias in the research of some archaeologists, but it is important to consider how these and other volcanic resources might have been used in everyday life (e.g., Jaime-Riveron 2016: 86). The consolidated volcanic ash in this region is referred …


Investigating The Distribution Of Soil Inorganic Carbon, And The Role Of Dust Deposition In Dryland Soils, Zahra Ghahremani 2024 Boise State University

Investigating The Distribution Of Soil Inorganic Carbon, And The Role Of Dust Deposition In Dryland Soils, Zahra Ghahremani

Boise State University Theses and Dissertations

The importance of dust deposition in the biogeochemical cycling of nutrients, sediment redistribution, and soil formation is well-known. Anthropogenic activities such as changing land use and agricultural practices can influence dust flux deposition rates, dust organic matter content, and the chemical composition of dust. This study examines the influence of agricultural activities on aeolian deposition in a the xeric intermontane westerns USA. We investigate seasonal and spatial variations in dust deposition rates, dust organic matter, dust inorganic matter, and dust geochemistry from passive dust traps. The Reynolds Creek Experimental Watershed (RCEW; Owyhee Mountains, Idaho) and the Northwest Irrigation and Soils …


Characterization Of Carbonaceous Fault Rocks, Pioneer Fault Zone, South-Central Idaho, Genna Baldassarre 2024 Utah State University

Characterization Of Carbonaceous Fault Rocks, Pioneer Fault Zone, South-Central Idaho, Genna Baldassarre

All Graduate Reports and Creative Projects, Fall 2023 to Present

Differing crystallinities of carbonaceous material are common in fault rocks across a range of geologic settings and spatial scales and may provide constraints on strain rate, the nature of fault slip, fluid-rock interactions, and temperature variations over the earthquake cycle. The Pioneer fault at Little Fall Creek in south-central Idaho provides an excellent opportunity to study nanostructure changes of carbonaceous matter as a function of fault deformation. At this location, the Pioneer Fault exhibits a well-defined principal slip zone (PSZ) composed of multi-layered white siliceous mineralization and black carbon to graphite with a continuously exposed adjacent damage zone that includes …


3d Analysis Of Fe-Ti Oxides And How They Affect Crystal-Plastic Deformation In Atlantis Bank, Southwest Indian Ridge, Sarah Hill 2024 The University of Southern Mississippi

3d Analysis Of Fe-Ti Oxides And How They Affect Crystal-Plastic Deformation In Atlantis Bank, Southwest Indian Ridge, Sarah Hill

Master's Theses

This project focuses on the importance of the relationship between Fe-Ti oxide abundance and interconnectivity, and crystal-plastic deformation in Atlantis Bank, Southwest Indian Ridge by utilizing Micro-CT scanning. This was done through comparing the Micro-CT scans of 15 samples from three different Ocean Drilling Program and International Ocean Discovery Program drill holes using the Nikon NIS Advanced Research 3-D visualization program and producing plots and statistics from MATLAB. Results indicate a wide range of textures across a range of crystal-plastic fabric intensity and Fe-Ti oxide abundance. Ultimately, there was a generally positive relationship between depth, CPF intensity, and Fe-Ti oxide …


Life On The Edge: The Cambrian Marine Realm And Oxygenation, Sara Pruss, Benjamin C. Gill 2024 Smith College

Life On The Edge: The Cambrian Marine Realm And Oxygenation, Sara Pruss, Benjamin C. Gill

Geosciences: Faculty Publications

The beginning of the Phanerozoic saw two biological events that set the stage for all life that was to come: (a) the Cambrian Explosion (the appearance of most marine invertebrate phyla) and (b) the Great Ordovician Biodiversification Event (GOBE), the subsequent substantial accumulation of marine biodiversity. Here, we examine the current state of understanding of marine environments and ecosystems from the late Ediacaran through the Early Ordovician, which spans this biologically important interval. Through a compilation and review of the existing geochemical, mineralogical, sedimentological, and fossil records, we argue that this interval was one of sustained low and variable marine …


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