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2025

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Articles 1 - 30 of 418

Full-Text Articles in Geology

Hydrothermal Vents In Sulfuric Acid Speleogenesis Karst: Isolated Feeders With Pristine Hypogenic Water Or Interconnected Conduits With Rapid Flow And Recycled Water?, Jakub Mareš, Marek Audy, Serban M. Sarbu, Jan Kukačka, Romeo Eftimi, Jiří Bruthans Dec 2025

Hydrothermal Vents In Sulfuric Acid Speleogenesis Karst: Isolated Feeders With Pristine Hypogenic Water Or Interconnected Conduits With Rapid Flow And Recycled Water?, Jakub Mareš, Marek Audy, Serban M. Sarbu, Jan Kukačka, Romeo Eftimi, Jiří Bruthans

International Journal of Speleology

Underwater connectivity and flow paths in the saturated zone of hypogenic sulfuric acid speleogenesis (SAS) karst remain unclear, despite sustained research over the past 30 years. Being regarded as sources of pristine H2S-charged water, narrow inflow conduits called "feeders" are typically considered primary sources of water and hotspots of speleogenesis. In southeastern Albania, there is a newly discovered active SAS karst system comprising numerous caves and springs. Tracer tests were conducted to investigate the connection of these caves to the surrounding springs and to characterize the flow paths. The results show that water flows from cave lakes to …


Aquifer Distribution In Lukobe Ward, Morogoro Municipality, Tanzania: Mapped Resources For Sustainable Water Access, Kelvin K. Kayuni Dec 2025

Aquifer Distribution In Lukobe Ward, Morogoro Municipality, Tanzania: Mapped Resources For Sustainable Water Access, Kelvin K. Kayuni

Tanzania Journal of Science

In response to the ongoing challenges posed by the scarcity of reliable fresh-water sources in Lukobe Ward, Morogoro Municipality, Tanzania, this study applied an integrated approach that combines geospatial and geophysical datasets to identify previously undocumented aquifers. The datasets utilized include an apparent density map generated from high-resolution GGMPlus satellite gravity data, a geological map (Quarter Degree Sheet 183), a water drainage map, and a slope map created from a digital elevation model (DEM). The analysis successfully identified four unconfined, saprolitic aquifers in the study area, designated as aquifers A, B, C, and D. These aquifers span areas of 12.2 …


A Cave In Miocene Conglomerate: The Törökpince-Abaliget Cave System, Hungary, Krisztina Sebe, Piroska Pazonyi, Márton Bauer, Bálint Szappanos, Márton Szabó, Zoltán Szentesi, Mihály Gasparik, Ákos Juhász, Luca Pandolfi, Máté Gregorits, József Haász, Ágnes Novothny, Zsófia Ruszkiczay-Rüdiger Dec 2025

A Cave In Miocene Conglomerate: The Törökpince-Abaliget Cave System, Hungary, Krisztina Sebe, Piroska Pazonyi, Márton Bauer, Bálint Szappanos, Márton Szabó, Zoltán Szentesi, Mihály Gasparik, Ákos Juhász, Luca Pandolfi, Máté Gregorits, József Haász, Ágnes Novothny, Zsófia Ruszkiczay-Rüdiger

International Journal of Speleology

Conglomerate caves are rare, and only a few have been described in the scientific literature. Here, we present a newly discovered and significant cave system in SW Hungary, comprising over 500 m of upper passages and a shorter, lower section of a through-cave developed in Lower–Middle Miocene conglomerates. The formation of these cave passages was controlled chiefly by bedding and fractures. Dissolution has produced typical karstification morphologies, whereas corrasion, granular disintegration, and rock collapse have also played a role in shaping the cave. The cave is dominated by vadose-zone morphologies, but sediment infills indicating upward water flow, along with ceiling …


Reconstructing Central American Hydroclimate Changes Across Time From Isotopic Signatures In Modern And Paleo-Rainfall Records, Giuseppe Lucia Dec 2025

Reconstructing Central American Hydroclimate Changes Across Time From Isotopic Signatures In Modern And Paleo-Rainfall Records, Giuseppe Lucia

UNLV Theses, Dissertations, Professional Papers, and Capstones

Tropical monsoon rainfall is a key component of Earth’s climate system and supports the livelihood and economy of billions of people. Yet, projections of future monsoons remain highly uncertain, particularly in regions with distinct physiography and complex land-ocean-atmosphere interactions like Central America, where long and continuous high-resolution paleoclimate data to test climate model simulations are still limited. This series of studies aims to reconstruct monsoon dynamics and underlying forcing controls in Central America on multiple timescales by the analysis and integration of stable isotope data in modern and paleo-rainfall records from Guatemala.

In Chapter 2, I present a daily-resolution, two-year-long …


Fault Structure, Deformation Mechanisms, And Why Fault Zones Matter To Society, Elizabeth S. Petrie, David A. Ferrill, Kelly K. Bradbury, James P. Evans Dec 2025

Fault Structure, Deformation Mechanisms, And Why Fault Zones Matter To Society, Elizabeth S. Petrie, David A. Ferrill, Kelly K. Bradbury, James P. Evans

Geosciences Faculty Publications

Faults are widespread geologic structures that form in sediment and all rock types, occur in all tectonic regimes, and can be a blessing or a curse to society. Faults and fault zones act as conduits for underground movement of water and as plumbing systems for aquifers and springs essential for human habitation in many semi-arid and arid regions worldwide. Faults also provide pathways for natural oil and gas migration and high-permeability zones in hydrocarbon reservoirs, as well as barriers contributing to trapping and reservoir compartmentalization. By enhancing permeability in many geothermal energy systems, faults can be essential for fluid circulation …


Dense Temporary Array Investigation Of Jemez Uplift Seismicity, Jillian D. Podmore Dec 2025

Dense Temporary Array Investigation Of Jemez Uplift Seismicity, Jillian D. Podmore

Earth and Planetary Sciences ETDs

A protracted multi-stage tectonic and magmatic evolution combined with low regional crustal strain rates make it challenging to characterize active structure that may host earthquakes in the Jemez Mountains of New Mexico. Here, we leverage temporary 1-month deployments of nodal seismometers to gain new insights into seismicity of the Jemez Mountains, which only have continuous seismic monitoring on their eastern flank as a result of the Los Alamos Seismic Network. Our catalog is built using 4 steps: phase picking in continuous seismic data, association of picks to detect unique events, event magnitude estimation, and absolute hypocenter estimation. We detect and …


Seismological Investigations Of Magmatic Systems Using Dense Nodal Arrays, Wenkai Song Dec 2025

Seismological Investigations Of Magmatic Systems Using Dense Nodal Arrays, Wenkai Song

Earth and Planetary Sciences ETDs

Understanding the internal architecture of magmatic systems is crucial for volcanology, yet conventional geophysical techniques often lack the resolution to image their fine-scale structures. This dissertation leverages unique datasets from dense nodal arrays to investigate the upper crustal magmatic systems beneath Yellowstone Caldera, Valles Caldera, and Mount St. Helens. At Yellowstone, I processed vibroseis data to delineate the top of the modern magma reservoir and evaluate the thermal connection between the magmatic and the overlying hydrothermal systems. At Valles, 3D radial seismic anisotropy imaging reveals strong positive radial anisotropy within the reservoir, indicating an organized structure of horizontally sill-like melt …


Contemporary Martian Geomorphic Processes And The Suitability Characterization Of Terrestrial Analogues, Daniel Paul Mason Dec 2025

Contemporary Martian Geomorphic Processes And The Suitability Characterization Of Terrestrial Analogues, Daniel Paul Mason

Earth and Planetary Sciences ETDs

Both historical and contemporary evidence for geomorphic activity on the surface of Mars is apparent. This evidence is showcased by features including a) well-preserved deltaic remnants in an otherwise cold and arid environment, present along the western flank of Jezero Crater, and b) the seasonal appearance of candidate recurring slope lineae throughout Martian equatorial, lower, and mid-latitudes as seen within both the Eos Chasma region and on the walls of Raga, Lohse, Rauna, and Tivat Craters. In this dissertation, I elucidate the role that geomorphic processes, whether aqueous or dry, have played in shaping both the ancient and contemporary Martian …


Mississippi River Pre-Loess Terrace Deposits: Distribution Of Aggregate Resources, Jonathan Leard Dec 2025

Mississippi River Pre-Loess Terrace Deposits: Distribution Of Aggregate Resources, Jonathan Leard

Theses and Dissertations

Pre-loess Terrace Deposits are a Pleistocene, high-quality aggregate resource of gravel, sand, and clay subjacent to loess of varying thickness along the eastern valley wall of the Yazoo Basin in Mississippi. This project delineated 1,230 mi2 of this resource with a volume greater than 33 billion yd3 from the misinterpreted Citronelle Formation in Desoto, Tate, Marshall, Panola, Tallahatchie, Yalobusha, Grenada, Carroll, Holmes, Yazoo, Madison, Hinds, Warren, Jefferson, Claiborne, Adams, Franklin, and Wilkinson Counties with nine terrace base levels at 40, 180, 220, 250, 270, 300, 330, 340, and 370 feet msl indicated by test holes, gravel mine data, outcrop studies, …


Collaborative Research: Evolution Of The Tristan-Gough-Walvis Ridge Hotspot System: Age And Composition Of Expedition 391/397t Volcanic Basement, Katherine Elizabeth Potter Dec 2025

Collaborative Research: Evolution Of The Tristan-Gough-Walvis Ridge Hotspot System: Age And Composition Of Expedition 391/397t Volcanic Basement, Katherine Elizabeth Potter

Funded Research Records

No abstract provided.


Collaborative Research: Rapid: Fault Rupture And Spring Sampling Of The 2023 Kahramanmaras, Turkey, Earthquake Sequence Ruptures, Alexis Ault, Dennis Lowell Newell Dec 2025

Collaborative Research: Rapid: Fault Rupture And Spring Sampling Of The 2023 Kahramanmaras, Turkey, Earthquake Sequence Ruptures, Alexis Ault, Dennis Lowell Newell

Funded Research Records

No abstract provided.


Stream Behavior Characterization Of Marin County Coastal Watersheds And Their Influence On Salmonid Habitat, Ellie L. Murdoch Dec 2025

Stream Behavior Characterization Of Marin County Coastal Watersheds And Their Influence On Salmonid Habitat, Ellie L. Murdoch

Master's Theses

Coastal watersheds in California are increasingly affected by climatic variability, threatening stream behavior, ecological function, and salmonid habitat suitability. This study evaluated streamflow behavior of seven watersheds in Marin County, California, with detailed analysis of Corte Madera, Olema, and Redwood watersheds, which are not influenced by reservoir releases. Using USGS stream gauge records, PRISM climate data, SSURGO soils, and geologic and vegetation information, streamflow metrics critical to salmonid life cycles were quantified for water years 2014 to 2023. Watersheds with greater storage capacity, such as Redwood, exhibited muted hydrologic responses, including delayed flow activation, lower peak flows, slower recession rates, …


A Study Of The Stratigraphic And Petrological Characteristics Of Section (10,323-10,325 Ft), Prevost 1- 11, Bay County, Michigan, Hajir Al Harthi Dec 2025

A Study Of The Stratigraphic And Petrological Characteristics Of Section (10,323-10,325 Ft), Prevost 1- 11, Bay County, Michigan, Hajir Al Harthi

Honors Theses

This study presents a detailed petrological characterization of a short core section (10,323-10,325 ft) from the Prevost 1-11, Bay County, Michigan. This work is part of a broader carbon capture, utilization, and storage (CCUS) project to determine whether the Glenwood Formation could be an effective confining unit (CU) for carbon dioxide (CO2) injection in the underlying St. Peter Sandstone. The methods used to collect petrological data include standard core description, Xray fluorescence spectroscopy (XRF), powder X-ray diffraction (XRD), thin section microscopy, and scanning electron microscopy (SEM) including backscattered electron (BSE), energydispersive X-ray spectroscopy (EDS), and secondary electron (SE) modes. These …


Structural Geology Of The Brady Mountain Area, Ouachita Mountains, Arkansas: Integrating Field Mapping, Geospatial Techniques, Photogrammetry And 3d Modeling For Structural Analysis, Emmanuel Darko, Zachariah Fleming Dec 2025

Structural Geology Of The Brady Mountain Area, Ouachita Mountains, Arkansas: Integrating Field Mapping, Geospatial Techniques, Photogrammetry And 3d Modeling For Structural Analysis, Emmanuel Darko, Zachariah Fleming

Electronic Theses and Dissertations

Much of the Ouachita orogenic belt, representing the deformed Paleozoic rocks flanking the southern margin of the North American craton, is buried beneath post-orogenic Mesozoic and Tertiary sediments composing the Gulf Coastal Plain. The Ouachita Mountains of Arkansas and Oklahoma are the largest areas of outcrop for the Pennsylvanian-age Ouachita orogenic belt, making it an ideal place to study the orogeny. This study focuses on the Brady Mountain area within the Benton Uplift, the orogenic core of the Ouachita Mountains in western Arkansas. The region is comprised of numerous ridges trending nearly east-west and are for the most part densely …


Reservoir Characterization Of The Clarksville Formation In Red River County, Texas, Matthew Allen Parker Dec 2025

Reservoir Characterization Of The Clarksville Formation In Red River County, Texas, Matthew Allen Parker

Electronic Theses and Dissertations

The Upper Jurassic Clarksville Formation in northern Texas and southern Oklahoma is a productive but poorly understood sandstone–conglomerate unit with unresolved questions regarding its depositional environment and sediment provenance. This study evaluates the depositional setting, spatial distribution, and diagenetic controls of the Clarksville Formation using integrated core and well log analyses in Red River County, Texas. Three cores (Lennox Unit #1, Reeder Oil Unit #2, and Reeder Oil Unit #7) were analyzed for lithology, mineralogy, porosity, permeability, and fluid saturation, and correlated with 137 well logs to map formation thickness and regional trends.

Four lithofacies were identified based on core …


Geochemical Analysis Of The Eagle Ford Shale In Webb And Dimmit Counties, Tx, Natalie G. Girlinghouse Dec 2025

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 …


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 Dec 2025

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 …


Spatial–Temporal Evolution Of The Box Springs Plutonic Complex, Riverside, Ca, Mateo Ospino Díaz Dec 2025

Spatial–Temporal Evolution Of The Box Springs Plutonic Complex, Riverside, Ca, Mateo Ospino Díaz

Loma Linda University Electronic Theses, Dissertations & Projects

The mechanisms of pluton emplacement into continental crust have long been debated in igneous geology, with early models emphasizing forceful processes such as ballooning, later contrasted by alternative emplacement mechanisms including diapirism, incremental assembly, stoping and, emplacement by sheets and dikes. These contrasting perspectives highlight the complexity of the construction of mid-crustal intrusions and the need for case studies that integrate multiple datasets. The Box Springs Plutonic Complex (BSPC) in the northern Peninsular Ranges Batholith (PRB) preserves structural, textural, and compositional features that record its emplacement and internal construction. Although its lithology, structure, and geochemistry have been described, an integrated …


Modeling The Greenland-Iceland-Faroe Ridge Using Integrated Geophysical Analysis, Zachary Clowdus Dec 2025

Modeling The Greenland-Iceland-Faroe Ridge Using Integrated Geophysical Analysis, Zachary Clowdus

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The Greenland-Iceland-Faroe Ridge (GIFR) is an area of significant geologic interest with anomalously thick crust related to enhanced melt generation from the interaction between the Mid-Atlantic Ridge and the Iceland hotspot. To the northeast of Iceland lies the Jan Mayen Microcontinent (JMMC), which is a continental fragment separated from Greenland during the opening of the Northern Atlantic. The overall extent of the JMMC, especially its southern boundary, remains poorly constrained. The crust beneath the GIFR is believed to be primarily of oceanic affinity. However, a recent discovery of felsic lavas in Iceland led to an alternative hypothesis that implies the …


Metal Zonation And Evolution Of The Bronson Slope Porphyry Cu-Au-Mo Deposit In The Iskut Region Of British Columbia, Canada, Luis Jacobo Yagual Dec 2025

Metal Zonation And Evolution Of The Bronson Slope Porphyry Cu-Au-Mo Deposit In The Iskut Region Of British Columbia, Canada, Luis Jacobo Yagual

Open Access Theses & Dissertations

Bronson Slope is a Cu-Au-Mo porphyry deposit located within the Stikine Terrane in the Golden Triangle District of northwestern British Columbia, Canada. This deposit represents a complex, multistage magmatic-hydrothermal system emplaced into sedimentary and volcanoclastic rocks of the Triassic Stuhini Group. Bronson has an inferred resource of 517.3 Mt at 0.33 g/t Au, and 0.09% Cu. This study integrates detailed and quick logging from 20 drill holes, totaling 20,296m, SWIR spectral analysis, ICP-MS geochemistry, XRF analysis, magnetic susceptibility measurements, geochronology, and 3D models developed in Leapfrog Geo which define the stratigraphy, intrusive geometry, extension, alteration footprint assemblage, metal zonation, and …


An Investigation Of Paleoclimate Through A Sedimentological Lens In The Gulf Of Mexico And Western North Pacific, Sarah Monica Dec 2025

An Investigation Of Paleoclimate Through A Sedimentological Lens In The Gulf Of Mexico And Western North Pacific, Sarah Monica

Dissertations

This dissertation explores the use of sediment cores as proxy data for the reconstruction of paleoclimatic and environmental conditions. Human-caused climate change is leading to dramatic shifts in the global climate. As the instrumental record of climate is relatively short compared to the amount of time Earth has experienced weather, this work aims to extend our knowledge of climate beyond the instrumental record, thereby improving our holistic understanding of the climate system. In Chapter one, sediment cores from the central Texas inner shelf are used to produce a record of intense tropical cyclone (TC) activity over a ~4500-year period. X-Ray …


Evidence Of Backwater Morphodynamics In Stratigraphy On Earth And Mars: Implications For Ancient Mars, Cory Mitchell Hughes Dec 2025

Evidence Of Backwater Morphodynamics In Stratigraphy On Earth And Mars: Implications For Ancient Mars, Cory Mitchell Hughes

Graduate Theses and Dissertations

Geologic evidence indicates that liquid water once flowed in abundance across the martian surface. For this reason, in the search for evidence of extraterrestrial life, Mars represents a prime target for scientific inquiry. River systems encode climatic and environmental signals in their deposits on Earth and Mars, often in fan-shaped landforms (e.g., alluvial fans, river deltas, etc.). Distal fan-shaped deposits (i.e., river deltas), in particular, act as a relatively high-fidelity record of dynamic geologic processes. As such, NASA frequently sends rovers to locations on Mars’ surface with hypothesized river deltas (e.g., Perseverance and Jezero crater). Problematically, there are many different …


East Antarctic Ice Sheet History At The Outback Nunataks Using Geographic Information Systems And Cosmogenic Dating, Jacob P. Baker Dec 2025

East Antarctic Ice Sheet History At The Outback Nunataks Using Geographic Information Systems And Cosmogenic Dating, Jacob P. Baker

Electronic Theses, Projects, and Dissertations

This study investigates the history of ice sheet surface elevation at the Outback Nunataks in East Antarctica using exposure age dating and geomorphic mapping. We identified glacial landforms at Roberts Butte, Miller Butte, and Frontier Mountain, in the Outback Nunatak range, using 2023 Landsat Image Mosaic of Antarctica (LIMA) and 2022 Reference Elevation Model of Antarctica (REMA). We collected bedrock and glacial erratic samples for cosmogenic nuclide analysis from Roberts Butte and Miller Butte during the 2023-24 United States Antarctic Program field season. Analysis of glacial erratics reflect inherited cosmogenic nuclide concentrations, resulting in apparent exposure ages between 359 and …


Groundwater Arsenic Contamination In The Oro Grande Wash, Dalila Boice Dec 2025

Groundwater Arsenic Contamination In The Oro Grande Wash, Dalila Boice

Electronic Theses, Projects, and Dissertations

This study investigates the distribution of naturally occurring arsenic in groundwater within the Oro Grande Wash in San Bernardino County, California. Depth-discrete groundwater quality data were collected over multiple years using nested and Westbay monitoring wells. Water quality results showed higher levels of arsenic in the deeper aquifers, ranging between 600 feet and 1,000 feet below ground surface. Arsenic levels in these regions reached as high as 66 µg/L. At roughly 800 feet and below, water quality data from the wells reveal that arsenic concentrations exceeded the 10 µg/L maximum contaminant level (MCL) in 87% of cases. These data provide …


Using Luminescence Of Quartz Temper From Archaeological Pottery To Infer Wildfire Intensity In The Southwestern Us, Brooklyn D. Dib Dec 2025

Using Luminescence Of Quartz Temper From Archaeological Pottery To Infer Wildfire Intensity In The Southwestern Us, Brooklyn D. Dib

All Graduate Theses and Dissertations, Fall 2023 to Present

The size and frequency of wildfires have increased recently, impacting ecosystems, communities, and human health. This research uses the heat-sensitive luminescence signals of quartz sand temper within archaeological pottery to record past wildfire conditions. Pottery sherds, which are fragments of archaeological pottery, from the forest floor in sites in New Mexico and Arizona were collected from different fire contexts (no fire exposure, historical fires, prescribed burns, and modern wildfires). These forests are primarily Ponderosa Pine with a grassy understory. The interior sand grains of each sherd sample were analyzed using optically stimulated luminescence, which dates when the mineral grains were …


Engineering Risk And Indigenous Resilience Toward Intelligent Decision Support For Mining In Ancestral Lands, Izech Brian O. Edwin, King Harold A. Recto Dec 2025

Engineering Risk And Indigenous Resilience Toward Intelligent Decision Support For Mining In Ancestral Lands, Izech Brian O. Edwin, King Harold A. Recto

Electronics, Computer, and Communications Engineering Faculty Publications

Mining within ancestral territories reveals an ongoing conflict between technical viability and Indigenous consent. This collaborative study, conducted by an engineering scholar and a policy researcher of Indigenous heritage in Benguet among the Ibaloi and Kankanaey peoples, investigates how risk transparency and policy alignment can bridge existing divides, while formulating principles applicable to other Indigenous mining contexts. The study provides an initial evaluation of the feasibility of a proposed large-scale mining operation within a risk-informed, data-driven governance framework. Three elements of engineering risk were assessed utilizing literature-derived and proxy parameters: (1) Land degradation is indicated by a Soil Productivity Index …


Updating The Surface Geological Maps In The Boston Mountains Region Of Arkansas Using Subsurface Well Log Correlation And Lidar Mapping, Olivia Smith Dec 2025

Updating The Surface Geological Maps In The Boston Mountains Region Of Arkansas Using Subsurface Well Log Correlation And Lidar Mapping, Olivia Smith

Graduate Theses and Dissertations

The Pennsylvanian Atoka Formation are the primary surface outcrops of the Boston Mountains in northwest Arkansas. Where fully preserved in the Arkoma Basin to the south, the Atoka Formation exceeds 18,000 feet of sandstone and shale. It is mapped as a single “undifferentiated” unit on the surface geological map of Arkansas. This project correlates ten subsurface subdivisions of the Atoka Formation plus the Desmoinesian to the surface outcrops of the southern Boston Mountains. This produced a higher resolution surface map beyond the current Atoka Undifferentiated scheme. Recognition of the Atoka Formation subdivisions in surface outcrops using standard lithostratigraphic and biostratigraphic …


An Integrated Lithospheric Geotherm Model From Seismic Data And Plate Ages, Amanda R. Leaman Dec 2025

An Integrated Lithospheric Geotherm Model From Seismic Data And Plate Ages, Amanda R. Leaman

All Graduate Theses and Dissertations, Fall 2023 to Present

This research aims to develop advanced methods to accurately depict temperature profiles within the lithosphere, the Earth’s rigid outer layer. These temperature profiles extend from Earth’s surface to the asthenosphere, the ductile layer below the lithosphere. Constraining the poorly-known temperature distribution within the upper Earth is important for modeling the deformation of Earth’s crust over varying timescales and is essential for advancing realistic simulations of Earth dynamics. Here, I utilize enhanced global seismic data, coupled with recent advances in our understanding of mineral systems, to create several global lithospheric models in which I estimate temperature profiles from seismically observable features …


Phase Equilibria Modeling Constraints On Channel Flow Of Metasedimentary Crust Beneath The Southeastern Tibetan Plateau, Govind Joshi, Gregory Dumond Nov 2025

Phase Equilibria Modeling Constraints On Channel Flow Of Metasedimentary Crust Beneath The Southeastern Tibetan Plateau, Govind Joshi, Gregory Dumond

Geosciences Faculty Publications and Presentations

Lower crust of the southeastern Tibetan Plateau includes 100 s of km2-scale zones of low resistivity at 20-40 km-depths indicating the presence of melt +/- fluid +/- graphite. These zones coincide with interconnected zones of low shear wave velocity. Data from central and southeastern Tibet support the occurrence of meta-sedimentary felsic granulites in the lower crust along a backarc-like geothermal gradient. Phase equilibria modeling of average metasedimentary pelite and greywacke bulk compositions constrained by these geophysical data explored the impact of partial melting on shear wave velocity for a range of fluid content. Low shear wave velocities beneath southeastern Tibet …


Controls On Speleothem Carbon Isotopes, Paloma Marcos Nov 2025

Controls On Speleothem Carbon Isotopes, Paloma Marcos

Undergraduate Research Symposium Posters

The Sistema Huautla cave system is the deepest known in the Western Hemisphere. It is located in the Sierra Mazateca Mountain Ranges near Jiménez de Huautla, Oaxaca. There are over 29 separately discovered entrances into this karst environment making it the 28th longest cave system in the world. It can be considered by some as one of the most complex vertical drainage systems on Earth. This extensive study site has been an area of interest among cavers and scientific researchers for nearly 6 decades. Speleothem samples from the study sites have been found to be over 433,000 years old. The …