Geology Commons^™

Geochemical And Petrological Observations Of The June Lake Basalt, Eastern California, Daniel Jacob Abel

Cal Poly Humboldt theses and projects

The June Lake basalt is a monogenetic cinder cone and 11-km-long lava flow in eastern California located ~10 km NW of the Long Valley caldera. The stratigraphic position of the June Lake basalt between Tahoe and Tioga glacial deposits suggests an eruption age of only ~20-45ka. This age places the June Lake Basalt among the youngest volcanic eruptions in the Long Valley-Mono Basin region, where volcanic activity spans from the late Pliocene to the Holocene. The goal of this study is to use field observations coupled with whole-rock and crystal geochemical analyses to investigate the magma source and pre-eruption magma …

The Effects Of A Microplate On Plume-Ridge Interactions: Constraints From Comparing Easter And Juan Fernandez Microplates In The Eastern Pacific Ocean, Katherine Ames, Jennifer Georgen

OES Faculty Publications

This study investigates the nature of plume-ridge interactions near a tectonic microplate using mantle Bouguer anomaly (MBA) gravity calculations. The focus of this investigation is a comparison of the Easter and Juan Fernandez microplates, which are located in the eastern Pacific Ocean along the Pacific, Nazca, and Antarctic plate boundaries. The microplates have several similar characteristics, including general size, time of formation, and clockwise rotation within the larger bounding mid-ocean ridge systems. Unlike the Juan Fernandez microplate, however, the Easter microplate is located near a mantle plume (Easter/Salas y Gomez). Previously published geochemical data suggest that material from this plume …

Deep Crustal Boundaries As Fluid Conduits: A Geochemical Investigation Of Mvt Mineralization In Kentucky And Beyond, Dairian Boddy M. Boddy

Theses and Dissertations--Earth and Environmental Sciences

Critical minerals are vital to the United States economy and national security, yet their supply chains are at risk. Common minerals in Mississippi Valley-type (MVT) deposits, such as sphalerite, galena, fluorite, and barite, host critical metals such as barium, gallium, germanium, and zinc, which are essential for energy technologies. An investigation of three MVT mineral districts in Kentucky elucidated previously unrecognized systematics, genetic relationships, and sources of ore components using stable and radiogenic isotope geochemistry, particularly from galena, sphalerite, barite, and gangue minerals (e.g., carbonates). The localization and dominant type of mineralization in each district are potentially influenced by deep …

Geochemical Analysis Of The Eagle Ford Shale In Webb And Dimmit Counties, Tx, Natalie G. Girlinghouse

Electronic Theses and Dissertations

The Late Cretaceous Eagle Ford Shale of South Texas is a mixed carbonate–siliciclastic succession that serves as both a prolific hydrocarbon source and reservoir. This study integrates chemostratigraphy, mineralogical analysis, and elemental ratio proxies to reconstruct depositional environments and assess controls on detrital influx, paleoproductivity, and redox conditions across multiple cores in Webb and Dimmit counties. Major, trace, and redox-sensitive elements were evaluated alongside Total Organic Content (TOC) and carbonate content to identify stratigraphic trends and environmental shifts.

Results reveal distinct geochemical signatures between the Upper and Lower Eagle Ford Shale, with the Lower Eagle Ford characterized by elevated Al-rich …

Geochemical And Stratigraphic Characterization Of The Morrison Formation And Cedar Mountain Formation Contact In The Island Park Quadrangle, Uintah County, Utah, Emily Mcdermott

All Graduate Theses and Dissertations, Fall 2023 to Present

The Upper Jurassic Morrison Formation and Lower Cretaceous Cedar Mountain Formation are among the richest sources of dinosaur fossils. Despite a 24-million-year gap in time (the Jurassic–Cretaceous unconformity), these formations are difficult to distinguish due to their similar rock types and colors. In Utah's Island Park quadrangle (IPQ), these formations are not separated on existing geological maps. This study focuses on identifying and understanding the formational boundary between them using field observations, stable isotope analysis, clay mineralogy, and chemical techniques such as X-ray diffraction (XRD) and X-ray fluorescence (XRF).

Unlike other areas where a conglomerate layer marks the boundary, the …

Characterization Of Residual Mineral Content Of Bauxite Stockpiles In Saline County, Arkansas: An Xrd Analysis Approach, Andrew Kaze Sezibera

Electronic Theses and Dissertations

The Saline Mining District of central Arkansas once led U.S. alumina production and hosts extensive bauxite and nepheline syenite deposits. With the depletion of highgrade ore, renewed interest in bauxite stockpiles has focused on critical mineral potential. Previous X-ray Fluorescence studies have identified critical elements in significant concentrations, including uranium (U), thorium (Th), gallium (Ga), molybdenum (Mo), and lanthanides (Ln). This study examines five stockpiles (SP1, Clay, SP2, SP3, and SP4) in Section 20 of the Aluminum Company of America (ALCOA) Saline County bauxite mine, using Xray Diffraction (XRD) on 25 samples to characterize mineral phases and compare them with …

Identifying Salt Suture Zones And Lithological Changes Of The Louann Salt In The Gulf Of Mexico Basin, La. U.S.A., Jamie Dale Singer

Electronic Theses and Dissertations

The Louann Salt, a key evaporite unit in the Gulf of Mexico Basin, influences salt tectonics, hydrocarbon migration, and basin evolution. This study examines Louann Salt deposition and deformation within the Puma Diapir, focusing on mineralogical, geochemical, and structural features of suture zones in three offshore wells (Puma 2(w), Puma 3, and Panther). Using drill cuttings, X-ray fluorescence (XRF), inductively coupled plasma mass spectrometry (ICP-MS), X-ray diffraction (XRD), well-log data, and 3D seismic interpretation, the study analyzed salt composition and suture formation. Results show the salt primarily consists of halite, with minor anhydrite, gypsum, and sylvite, indicating continuous precipitation. Geochemical …

A Mineralogical And Geochemical Investigation Of The Influence Of Tectonic Setting On Accessory Mineral Assemblages In Serpentinites Along The Western North American Margins, Bryan H.T. Seymour

Electronic Theses, Projects, and Dissertations

Serpentinites are metamorphic rocks typically produced by hydrating mantle peridotites to form assemblages containing one or more serpentine minerals. They occur in various tectonic and geologic settings, such as submarine hydrothermal systems, ophiolite sequences, and the forearc mantle. Serpentinites are associated with highly reduced conditions, as indicated by low oxygen fugacity (ƒO₂) values. Previous investigations suggest that oxygen fugacity varies with tectonic setting due to differences in environmental conditions. To test this hypothesis, we analyzed serpentinites from a wide variety of tectonic settings in western North America: The New Idria forearc diapir (CA), Canyon Mountain Island arc complex (OR), Josephine …

Geochemical Analysis For Potential Critical Mineral Resources In Carbon Fly Ash, Korei D. Patterson Teer

Graduate Theses and Dissertations

The growing demand for critical minerals, coupled with the increasing supply chain vulnerabilities, has intensified the need for alternative domestic resources of critical minerals beyond traditional mining. Many of these critical minerals are essential for advanced technologies, energy storage, and national security, yet the United States remains heavily dependent on foreign imports, particularly from China. This study evaluates the economic potential of critical mineral recovery from Carbon Fly Ash (CFA), a byproduct of coal combustion, to determine its viability as a secondary source of critical minerals. A geochemical and mineralogical assessment was conducted on CFA samples from various storage sites …

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.

Geochemical And Sedimentological Signals Of Bottom Water Oxygen Dynamics From Lake Tanganyika (Zambia), Njahi Mwangala

Theses and Dissertations--Earth and Environmental Sciences

Lake Tanganyika is a large, ancient freshwater body with exceptional biodiversity that is located in the East African Rift System. Lake Tanganyika’s size and longevity make its sedimentary record useful for understanding environmental changes that cross spatial and temporal boundaries. Lake Tanganyika is known to be susceptible to global warming given its tropical location. Over 12 million people living within Lake Tanganyika’s watershed rely on fishing for their income and nutrition. Changes to limnological function driven by climate could therefore have serious implications for human health and biodiversity conservation. This study focuses on using geochemical properties of modern lake bottom …

Late Holocene Paleolimnology Of Lake Tanganyika (East Africa), Leandro Domingos Luz

Theses and Dissertations--Earth and Environmental Sciences

Understanding the long-term responses of ecosystems to climate variability is crucial for predicting and mitigating future changes in the Afrotropics, a region where a significant portion of the population is highly vulnerable to extreme climatic events. Lake Tanganyika, the largest rift lake in East Africa, offers a unique sedimentary archive that can be used to investigate the limnological changes, hydroclimatic shifts, and vegetation dynamics across various timescales. A multi-proxy approach was employed to assess the landscape responses to hydroclimatic fluctuations in the Late Holocene, integrating paleoenvironmental records from radiocarbon-dated sediment cores. This approach involved sedimentology, mineralogy, geochemistry, phytolith analysis, and …

Origins And Mechanisms Of Mobility Of Geogenic Arsenic Contamination In Toutle And Silver Lake, Wa, Usa, William A. Hays

All Master's Theses

Arsenic (As), a common contaminant in groundwater, is toxic to human health and has a maximum contaminant level of 10 ppb set by both the World Health Organization and the U.S. Environmental Protection Agency (ATSDR, 2007). In Toutle, WA, USA (30 km west of Mount Saint Helens), a private well, labelled TOU1, was previously identified with ~670 ppb of As and was the impetus of this study. This study targeted private wells in the vicinity of TOU1 to identify the extent of the arsenic contamination, identify the aquifer(s) of concern, and identify the mechanism(s) of mobility.

The wells were screened …

Zircon Age And Oxidation State Estimates For Plutons Spatially Associated With Mineral Deposits Along The Kettle Detachment Fault In The Orient Quadrangle, Northeastern Washington, Karla Ortega

All Master's Theses

Critical minerals are essential to national security, economic stability, and the transition to clean energy, making them a priority in geologic research and exploration. To better understand the magmatic conditions associated with critical mineral concentration, zircon, a recorder of magmatic history, was analyzed using U-Pb geochronology and trace element geochemistry. The analyses were conducted via LASS-ICP-MS on ten plutonic samples from the Orient quadrangle in northeastern Washington and one sample from the Adams Mountain and Hunter (AMH) quadrangles to constrain the geological processes leading to ore deposit formation, including tungsten (W). This region, cut by the Kettle Detachment fault, is …

Assessing Potential For Managed Aquifer Recharge On The Manastash Alluvial Fan: A Geochemical Analysis, Elif A. Myers

All Master's Theses

In south-central Washington, the Yakima River Basin spans 6,100 square miles, encompassing approximately 10% of the state. With a growing population and over 400,000 acres of irrigated cropland, reliable water availability is vital for supporting agricultural irrigation, municipal needs, and aquatic habitats. To ensure water for future use, Managed Aquifer Recharge (MAR), the practice of applying surface water to aquifers for storage or hydrologic system benefit, has been proposed within the Yakima Basin Integrated Plan (YBIP). This research explores the Manastash alluvial fan–located west of Ellensburg, Washington as a potential region for two MAR methods: Shallow Aquifer Recharge (SAR) and …

Oil-Oil Correlation Across Sedimentary Basins In Kansas Using Molecular Geochemistry And Fourier Transform Infrared Spectroscopy, Oluwaseun V. Omoyemi

Master's Theses or Doctor of Nursing Practice

Hydrocarbons are produced from different subbasins and stratigraphic intervals in Kansas. However, the geochemical characteristics and sources of these hydrocarbons are still poorly understood. While reservoir rocks, seals, and traps that are essential for petroleum systems are well defined within the state, the possible source rocks are often considered thermally immature, raising questions about their ability to generate the volume of hydrocarbons currently being produced. This research project tries to evaluate the geochemical characteristics of hydrocarbons produced in the state of Kansas and determine if the hydrocarbons from the different subbasins and stratigraphic units are genetically related. Thirty-seven crude oil …

Geochemical Evidence Of Drying During The 4.2 Ka Event In Sediment Cores From The Yucatán Peninsula, Mexico, Derek K. Gibson, Jonathan Obrist-Farner, Alex Correa-Metrio, Alejandra Rodriguez-Abaunza, Carlos Castañeda-Posadas

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Tropical hydroclimate variability during the Middle and Late Holocene was investigated using geochemical indicators of local-scale precipitation and evaporation preserved in sediment cores from two sites in the Mexican Yucatán Peninsula. Scanning X-Ray fluorescence spectroscopy data show generally decreasing precipitation trends during the Early and Middle Holocene. During the transition between the Middle and Late Holocene, geochemical evidence of reduced watershed erosion and increased evaporation indicate that a centennial-scale drying event impacted the region between 4.3 and 4.0 ka (kilo-anum; thousand years before present). These findings suggest that the 4.2 ka drying event, which has been previously recorded in Europe, …

Heavy Metals In Rural Soils: A Case Study In Jennings County, Indiana, Madeline Hill

All-Inclusive List of Electronic Theses and Dissertations

Heavy metals, such as lead and mercury, can be toxic if exposure levels are too high. People are often concerned about lead exposure from water or paint, but soil is another potential exposure avenue for many metals. While some heavy metals, including mercury and lead, are found in emissions from coal-burning power plants and from incinerators, many metals accumulate in soils from past uses (ex. lead paint, leaded gasoline, chemical spills, industrial emissions, and natural occurrences). It is important to have soil tested to check metal concentrations because consumption or inhalation of these metals can lead to permanent damage and …

Hydrogen Stable Isotope Constraints On Hydration Of Colorado Plateau Lower Crust From Oligocene-Miocene Navajo Volcanic Field Xenoliths, Shelby Dianne Litton

All Graduate Theses and Dissertations, Fall 2023 to Present

Understanding flat-slab subduction is crucial as it involves the horizontal movement of an oceanic plate beneath a continental margin over a long distance. This tectonic process is widespread yet not fully understood, particularly regarding how it influences the chemical makeup of the continental plate and recycling in the hydrosphere. By analyzing isotopes, which are variations of certain elements found in minerals and water, we can gain insights into the sources of chemicals and geological processes at play. Our study area included six locations within the Navajo volcanic field (NVF), a region in the Colorado Plateau. We analyzed 23 lower crustal …

Shaking Off The Rust: Unraveling The Depositional And Diagenetic History Of Enigmatic Ferroan Dolostones In The Cambrian Bright Angel Formation, Tonto Group, Grand Canyon, Joseph J. Clevenger

All Graduate Theses and Dissertations, Fall 2023 to Present

Within the siliciclastic-sediment-dominated Bright Angel Formation (BAF) of the iconic Cambrian sedimentary strata (Tonto Group) in Grand Canyon National Park, Arizona, workers have identified and named prominent reddish-brown cliffs breaking up the generally slope-forming unit near, but separated from, its upper contact with the limestone-dominated Muav Formation, the "Rusty Brown Dolostones" (RBDs). Previous hypotheses suggest that the RBDs are chemically and physically altered tongues of the Muav Formation intercalated with the BAF at increasingly higher stratigraphic positions from west to east within the Canyon. A genetic association between the Muav Formation and the RBDs, as well as between the RBDs …

New Insights Into The Diverse Intraplate Volcanism Present Within The Howland And Baker Island United States Exclusive Economic Zone, Nicholas Foresta

UNLV Theses, Dissertations, Professional Papers, and Capstones

The origin of oceanic volcanism has been attributed to various mechanisms, such as upwelling mantle plumes, lithospheric extension driven decompression melting, and small-scale convective cells in the asthenosphere. Discovering the range of magmatic drivers present in the ocean basins aids in understanding mantle geodynamics and tectonic processes. A recent seafloor exploration campaign within the Howland and Baker Island (HBI) U.S. Exclusive Economic Zone (EEZ; approximately near the equator and the International Date Line) resulted in the collection of multiple lava flow samples, which offer valuable insights into the complex origins and dynamics of intraplate seamounts. According to current absolute plate …

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 …

Petrologic And Geochemical Constraints On The Pre-Eruptive Storage Conditions Of Magmas Erupted During The ~12.5 Ka Flare Up Of Medicine Lake Volcano, Ca, Regina M. Khoury

Cal Poly Humboldt theses and projects

The Medicine Lake Volcano (MLV) system in the California Cascades is composed of a large shield volcano with numerous basaltic to rhyolitic vents on and around the flanks, many of which are aligned with N-S trending normal faults. A significant portion of the post-glacial volcanic activity at MLV is comprised of the ~12.5 ka “flare up” eruptions of basalt and basaltic andesite magmas from seven discrete flank vents. Prior work documented surface areas (0.02-198 km²), volumes (0.0001-4.35 km³), and eruption styles (Hawaiian to Strombolian; Donnelly-Nolan, 2010) of the ~12.5 ka deposits. This study uses new geologic …

Geographically Dependent Thermodynamic And Geochemical Evolution In The Post-Batholith Upper Mantle Beneath The Sierra Nevada: Analysis Of The Blue Knob Xenoliths, Eleanor Ruos

Scripps Senior Theses

Xenoliths entrained in recent (Miocene) volcanics from the Sierra Nevada provide insights into a continuously evolving upper mantle during post-batholith generation periods (early Cenozoic–present). Hypothesized mantle refertilization followed by subsequent delamination of the lithospheric root beneath the Sierra provides a contextual framework for analyzing how the upper mantle responds to such events. This study contributes new geochemical data from the ultramafic xenoliths of Blue Knob, including bulk-rock major and trace element data, thin-section petrography, mineral chemistry and thermobarometry, and oxygen isotopes (delta¹⁸O). Blue knob (Eastern Sierra) data are compared to previous works on xenoliths from Chinese Peak and …

Million-Year Melt-Presence In Mogollon-Datil Volcanic Field Rhyolites: Constraining The Histories Of The Bursum Caldera Resurgent Domes, Ethan Wagner

Graduate Theses/Dissertations

The Mogollon-Datil volcanic field which is located in southwestern New Mexico, is the result of punctuated volcanism and the transition between arc and rift magmatism. The resurgent domes within the 28 Ma Bursum caldera records the transition from rhyolitic to basaltic andesite volcanism that occurred between 27-26 Ma. Using a combination of new zircon U-Pb ages using chemical abrasion isotope dilution thermal ionization mass spectrometry (CA-ID-TIMS) with zircon U-Pb geochronology and trace element contents by laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) and whole rock and mineral trace element contents and isotope geochemistry this study investigates the temporal and …

Environmental Fate Of Sulfur In Sulphur Creek, Valles Caldera, Nm: Implications For Metal Transport And Water Quality, Daniel Lavery

Earth and Planetary Sciences ETDs

The 1.2 Ma Valles Caldera in north-central New Mexico hosts a young igneous volcanic hydrothermal system after the model proposed in Goff and Janik (2000). The Sulphur Springs area within Valles Caldera is an acid-sulfate area typical of this model, discharging acidic waters (pH 1.5-3) formed by oxidation of magmatic H₂S at the surface. We report on samples obtained from springs and streams collected between October 2021 and May 2023 in the Sulphur Creek and Alamo watersheds. Sulphur Creek receives input from Sulphur Springs and exhibits low pH (2-4) and high concentrations of Al (≤110 mg/L), Fe (≤60 …

Landscape/Atmosphere Interactions And Carbon-Dioxide Dynamics In The Great Onyx Groundwater Basin, Mammoth Cave National Park, Kentucky, Meghan Raines

Masters Theses & Specialist Projects

An increase in atmospheric CO2 since the Industrial Revolution has altered rates of global climate change and has motivated a need to better quantify the flux of carbon between Earth’s reservoirs. Attempts to quantify the exchange of atmospheric carbon between sources and sinks have led to an increasing interest in the terrestrial landscape, including the continental carbon sink associated with carbonate-mineral dissolution. This research sought to better inform an understanding of karst landscapes and their relationship with global climate change through carbon cycling. The study utilized high-resolution data collection of pH, temperature, and specific conductance of waters in the Cascade …

Trace Metal Analysis Of Pond Sediments To Measure Deposition From A Coal-Fired Power Plant In Ackerman Mississippi, Charles Bills

Theses and Dissertations

Trace element sediment pollution due to coal power plants have been reported in many countries. In this study, pond sediment samples collected from locations around a coal fired power plant in Ackerman, MS, were evaluated for their trace element concentration and pollution status. The samples were collected at two depths to study changes in element accumulation over time. The samples were digested and the elements, As, Cd, Cr, Cu, Pb, Hg, and Zn were analyzed using ICP-MS. Results were then compared to known background concentrations as well as sediment quality guidelines and pollution thresholds. The sample locations downwind of the …

Rift-Induced Disruption Of Cratonic Keels Drives Kimberlite Volcanism, Thomas M. Gernon, Stephen M. Jones, Sascha Brune, Thea K. Hincks, Martin Palmer, John C. Schumacher, Rebecca M. Primiceri, Matthew Field, William L. Griffin, Suzanne Y. O'Reilly, Derek Keir, Christopher J. Spencer, Andrew S. Merdith, Anne Glerum

Geology Faculty Publications and Presentations

Kimberlites are volatile-rich, occasionally diamond-bearing magmas that have erupted explosively at Earth’s surface in the geologic past^1,2,3. These enigmatic magmas, originating from depths exceeding 150 km in Earth’s mantle¹, occur in stable cratons and in pulses broadly synchronous with supercontinent cyclicity⁴. Whether their mobilization is driven by mantle plumes⁵ or by mechanical weakening of cratonic lithosphere^4,6 remains unclear. Here we show that most kimberlites spanning the past billion years erupted about 30 million years (Myr) after continental breakup, suggesting an association with rifting processes. Our dynamical …

Hydrology Data For Fern Cave, Alabama (2020-2022), Benjamin Tobin, Benjamin V. Miller, Matthew Niemiller, Andrea Erhardt

Research Data--KGS

Dataset includes water level from four sites within Fern Cave in Jackson County Alabama. Additionally, it includes chemistry of water, sediments and cave-adapted isopods.