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Terrane Accretion In The Trollheimen And Dovrefjell Regions Of The Scandinavian Caledonides, Norway, Stephanie Georgevich 2025 University of Texas at El Paso

Terrane Accretion In The Trollheimen And Dovrefjell Regions Of The Scandinavian Caledonides, Norway, Stephanie Georgevich

Open Access Theses & Dissertations

Following closure of the Iapetus Ocean, the paleocontinents of Laurentia and Baltica collided to form the Caledonian Orogeny. During this closure and subsequent collision, island arc terranes and microcontinents were accreted and subducted underneath the Norwegian continental margin. These terranes are preserved in central Norway, specifically in the Dovrefjell and Trollheimen mountain ranges. The order in which these terranes accreted to the continent and when this occurred is not well understood. To determine this stacking order, I will be using P-T path modeling, U-Pb zircon dating, and structural position. Knowing the degree, progression, and geologic age of metamorphism, and tectonostratigraphic …


Diagenesis And Controls On Porosity And Permeability In The Upper San Andres Formation Of West Texas, Jack Butcher 2025 Stephen F Austin State University

Diagenesis And Controls On Porosity And Permeability In The Upper San Andres Formation Of West Texas, Jack Butcher

Electronic Theses and Dissertations

West Texas reservoirs on the Central Basin Platform (CBP) are dominated by Permian-age carbonate deposits, significantly contributing to petroleum production. The Upper Permian-aged San Andres Formation, composed primarily of dolomite and limestone, is a prolific reservoir. This study assesses diagenetic influences on porosity and permeability within the San Andres Formation along the northern CBP. Two cores from the Monument 4-2 and Peterson 1 wells in West Texas were analyzed using core descriptions, thin section petrography, XRD, XRF, and MICP. Results indicate that dolomitization enhances porosity, with intercrystalline and moldic porosity being dominant, while late-stage cementation and compaction reduce permeability. XRD …


Mantle Flow And Crustal Deformation Revealed By Seismic Anisotropy In The Subduction Zone Beneath Myanmar, Enbo Fan, Mingming Jiang, Yinshuang Ai, Stephen S. Gao, Kelly H. Liu, Yumei He, Yiming Bai, Guangbing Hou, Yuan Ling, Chit Thet Mon, Myo Thant, Kyaing Sein 2025 Missouri University of Science and Technology

Mantle Flow And Crustal Deformation Revealed By Seismic Anisotropy In The Subduction Zone Beneath Myanmar, Enbo Fan, Mingming Jiang, Yinshuang Ai, Stephen S. Gao, Kelly H. Liu, Yumei He, Yiming Bai, Guangbing Hou, Yuan Ling, Chit Thet Mon, Myo Thant, Kyaing Sein

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The oblique convergence of the Indian and Eurasian plates drives significant deformation in the crust and mantle beneath Myanmar. However, the crustal deformation in the Indo-Burman Ranges (IBR) and mantle flow beneath Myanmar and adjacent areas remain unclear due to limited studies. We utilized data from the newly deployed second phase of the China-Myanmar Geophysical Survey of the Myanmar Orogen array to perform shear wave splitting analysis of PKS, SKKS, and SKS (XKS) phases. Our results, together with previous findings, provide new insights into mantle flow and crustal deformation across central Myanmar. In the IBR, we observed a transition from …


Cooling Climate Across Last Interglacial High Stands On San Salvador And Great Inagua, The Bahamas, Ian Winkelstern, Sierra Petersen, H. Allen Curran, Cecilie Phillips, Alex Quizon, Bosiljka Glumac, David Griffing 2025 Grand Valley State University

Cooling Climate Across Last Interglacial High Stands On San Salvador And Great Inagua, The Bahamas, Ian Winkelstern, Sierra Petersen, H. Allen Curran, Cecilie Phillips, Alex Quizon, Bosiljka Glumac, David Griffing

Geosciences: Faculty Publications

The last interglacial (LIG) is the last time global climate was about as warm as today, with global sea-levels several metres higher. The LIG probably had a re- duced latitudinal temperature gradient, with warmer poles and cooler tropics than today. Well-constrained records from low latitudes can test this overall model. We used bivalve shells sampled from six localities thought to expose the LIG age Cockburn Town Member of the Grotto Beach Formation on both San Salvador and Great Inagua Islands, The Bahamas. Previous work described two LIG depositional intervals: older ‘Reef I’ and younger ‘Reef II’, separated by a disconformity. …


Kinematic Representations Of Viscoelastic Postseismic Deformation, John Loveless, Brendan J. Meade 2025 Smith College

Kinematic Representations Of Viscoelastic Postseismic Deformation, John Loveless, Brendan J. Meade

Geosciences: Faculty Publications

Abstract Following large earthquakes, viscoelastic stress relaxation may contribute to postseismic deformation observed at Earth's surface. Mechanical representations of viscoelastic deformation require a constitutive relationship for the lower crust/upper mantle material where stresses are diffused and, for non‐linear rheologies, knowledge of absolute stress level. Here, we describe a kinematic approach to representing
geodetically observed postseismic motions that does not require an assumed viscoelastic rheology. The core idea is to use observed surface motions to constrain time‐dependent displacement boundary conditions applied at the base of the elastic upper crust by viscoelastic motions in the lower crust/upper mantle, approximating
these displacements as …


Explainable Machine Learning Surrogate Modeling For Exit Gradient Prediction In Hydraulic Structures Using Numerical Simulations, Prayas Rath, Jianting Zhu, Kevin M. Befus 2025 University of Wyoming

Explainable Machine Learning Surrogate Modeling For Exit Gradient Prediction In Hydraulic Structures Using Numerical Simulations, Prayas Rath, Jianting Zhu, Kevin M. Befus

Geosciences Faculty Publications and Presentations

Accurate prediction of exit gradients is essential for designing impounding hydraulic structures, such as dams and levees, to mitigate seepage-induced piping failures. Conventional analytical methods often neglect boundary effects and anisotropy, limiting their applicability in complex geological settings. This study develops an XGBoost-based machine learning surrogate model trained and tested on 8,000 MODFLOW numerical simulations to predict exit gradients under varying hydraulic and geological conditions. The data set covers numerous parameters, including anisotropy, head differences, structure width, cut-off wall depth, aquifer thickness, and uninterrupted riverbed length. The coefficient of determination for test data is 0.88, demonstrating reliable exit gradient prediction …


A Multi-Source Remote Sensing-Based Geocommunication Tool For Global Flood Monitoring And Management, Ebrahim Hamidi, Brad Peter, Hamed Moftakhari, Hamid Moradkhani 2025 University of Alabama - Tuscaloosa

A Multi-Source Remote Sensing-Based Geocommunication Tool For Global Flood Monitoring And Management, Ebrahim Hamidi, Brad Peter, Hamed Moftakhari, Hamid Moradkhani

Geosciences Faculty Publications and Presentations

Global warming is expected to increase the frequency of extreme flooding, making rapid and accurate flood mapping crucial for effective risk assessment. Many governmental agencies and organizations are developing flood risk assessment tools; however, due to the lack of observational records, some rely on probabilistic generated data, uncalibrated simulations, or terrain-based methods, all of which are subject to various types of uncertainty. Although remote sensing provides valuable flood data with global coverage, single-source reliance is constrained by satellite revisit rates, resolution, weather conditions, and sensor limitations. To address these challenges, this study introduces a user-friendly application on the Google Earth …


Measuring The Impact On Landscape And Sediment Transport Of Climate And Anthropogenic Influence In The Mississippi River Since 2000 Bce, Bailey Wycoff 2025 Louisiana State University and Agricultural and Mechanical College

Measuring The Impact On Landscape And Sediment Transport Of Climate And Anthropogenic Influence In The Mississippi River Since 2000 Bce, Bailey Wycoff

LSU Master's Theses

Understanding river dynamics is crucial to being able to interpret the geological history preserved in sediment deposited on continental margins, deltas, and alluvial plains. Sediment buffering can be a key control on the sediment flux to the ocean and involves sediment storage and recycling in flood plains. The efficiency of the transport varies depending on climatic and more recently anthropogenic influences. Sediment moving through meandering streams may be temporarily deposited in a point bar on the convex side of a meandering river. Meanders are sometimes cut off, creating an oxbow lake and filled in. The area of study, False River, …


Using Triple Oxygen Isotopes To Investigate Water Usage In Desert Ecosystems, Cloe V. Knutson 2025 University of New Mexico

Using Triple Oxygen Isotopes To Investigate Water Usage In Desert Ecosystems, Cloe V. Knutson

Earth and Planetary Sciences ETDs

In arid environments, maintaining water balance can be more critical for survival than obtaining food. As droughts intensify, understanding how animals manage body water is essential. Triple oxygen isotope analysis provides a novel way to trace water sources in animals, distinguishing contributions from free water, food-derived oxygen, and atmospheric O2. We developed an equilibration method using CO2–H2O oxygen exchange and measured δ’18O and Δ’17O values via tunable infrared laser direct spectroscopy (TILDAS). Validated against traditional fluorination methods, this technique enables streamlined analysis of whole blood and plant samples. Applied to …


Deformation And Earthquake Potential On The North America - Caribbean - Cocos Triple Junction In Guatemala, Jeremy Maurer, Andreas Eckert, Qiaoqi Sun, Jonathan Obrist-Farner 2025 Missouri University of Science and Technology

Deformation And Earthquake Potential On The North America - Caribbean - Cocos Triple Junction In Guatemala, Jeremy Maurer, Andreas Eckert, Qiaoqi Sun, Jonathan Obrist-Farner

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The triple junction between the Cocos (CO), North American (NA), and Caribbean (CA) tectonic plates in Guatemala is a region of high seismic risk and includes many large faults and historic earthquakes. Previous analyses of the tectonic system have been overly simplified, resulting in discrepancies between geologically derived and geodetic models of fault slip rate. This study leverages available geodetic, seismic, and geologic data to develop new strain rate maps and faulting models for the region. We find that locking on the regional faults matches historic reports of large earthquakes and that multiple minor fault segments are active and accommodate …


Unusually Preserved Benthic Foraminiferal Assemblages From The Lower Triassic Virgin Limestone Member, Moenkopi Formation, Nevada, U.S.A, Sara B. Pruss, Teagan E. McGuire 2025 Smith College

Unusually Preserved Benthic Foraminiferal Assemblages From The Lower Triassic Virgin Limestone Member, Moenkopi Formation, Nevada, U.S.A, Sara B. Pruss, Teagan E. Mcguire

Geosciences: Faculty Publications

The end-Permian mass extinction, the largest in Earth’s history, was so severe that biotic recovery was delayed for five or more million years. During the Early Triassic, ecosystems were populated by low diversity fauna, and the taphonomy of some fossil groups was reminiscent of Cambrian small shelly-style preservation. Herein we report a new assemblage of benthic foraminifera from the Lower Triassic (Olenekian, Spathian) Virgin Limestone Member, Moenkopi Formation in southern Nevada. Insoluble residues of carbonate samples produced >80 benthic foraminiferal tests, preserved as apatite- and iron oxide-internal molds. Dominant morphological groups include planispiral evolute forms, uniserial forms with round chambers, …


Edmore And Webster Coulee Hydrologic Simulation Data, Sharhad Wainty, Taufique H. Mahmood 2025 University of North Dakota

Edmore And Webster Coulee Hydrologic Simulation Data, Sharhad Wainty, Taufique H. Mahmood

Datasets

The authors compiled a hydrologic model for the Edmore at Edmore and Edmore at Webster Coulee Basin using Cold Region Hydrologic Platform. The datasets include observed and simulated streamflow, observed climatic data, land use maps and hydrological representative unit maps (HRU) maps. This study detected a mechanism of hydrologic change to wetting using a cold region hydrologic model during 1991-2024 period.


Study Of Anomalous Variations In Seismic And Non-Seismic Parameters Using Machine Learning Techniques To Develop The Earthquake Forecasting Model In The Himalayan Belt, Senthil Kumar M 2025 SASTRA Deemed to be University

Study Of Anomalous Variations In Seismic And Non-Seismic Parameters Using Machine Learning Techniques To Develop The Earthquake Forecasting Model In The Himalayan Belt, Senthil Kumar M

Theses and Dissertations

Understanding and forecasting earthquakes is not just about science it’s about saving lives, even as the dynamic and hidden nature of Earth's tectonic processes makes this an intricate challenge. The Himalayan belt is one of the most seismically active regions globally due to the collision of the Indian and Eurasian tectonic plates. Investigating this region is essential for understanding highly complicated tectonic mechanisms and reducing substantial hazards posed to millions of people by persistent and intense seismic events. This study aims to enhance forecasting methodologies by applying machine learning techniques while dealing with the inherent challenges of geological complexity and …


One Year Of Analysis Of Pfas Contamination In Surface Waters Of The West Plains Region Of Spokane County, Jerusha R. Hampson 2025 Eastern Washington University

One Year Of Analysis Of Pfas Contamination In Surface Waters Of The West Plains Region Of Spokane County, Jerusha R. Hampson

2025 Symposium

The West Plains has been significantly impacted by PFAS contamination due to the decades-long use of aqueous film-forming foam (AFFF) for firefighting training at both Fairchild Air Force Base (FAFB) and the Spokane International Airport (SIA). Groundwater contamination is significant, but less work had been done to understand contamination in surface waters. We now have over a year of data with most locations were sampled seasonally. Though FAFB and SIA are likely sources for some of the contamination, other, smaller sources exist. Surface waters are important to study as they form the boundaries of the West Plains and often function …


The Kentucky Microbiome Dataset, Rachel L. Washburn, Douglas C. Curl 2025 University of Kentucky

The Kentucky Microbiome Dataset, Rachel L. Washburn, Douglas C. Curl

Research Data--KGS

The Kentucky Microbiome Dataset is a continuously updated geolocated dataset which describes the distribution and diversity of microorganisms across the Commonwealth of Kentucky. Each geolocated point represents a location reported in the peer-reviewed literature where microorganisms were sampled from soil, water, geologic substrates, or clinical settings. Environmental studies include only non-host-associated, non-clinical microorganisms sampled from natural environments. Clinical studies are mapped separately to highlight locations where investigations into host-associated or human health-related microbes have occurred.

For each location, associated metadata include study information, taxonomic classifications, sample type, sampling method, latitude and longitude, sampling date, publication reference, and a direct link …


Framework For Mapping Sublimation Features On Mars’ South Polar Cap Using Object-Based Image Analysis, Racine D. Cleveland, Vincent F. Chevrier, Jason A. Tullis 2025 University of Arkansas, Fayetteville

Framework For Mapping Sublimation Features On Mars’ South Polar Cap Using Object-Based Image Analysis, Racine D. Cleveland, Vincent F. Chevrier, Jason A. Tullis

Geosciences Faculty Publications and Presentations

Mars’ south polar cap hosts dynamic landforms known as Swiss cheese features (SCFs), which form through the sublimation of carbon dioxide (CO2) ice driven by the planet’s extreme seasonal and diurnal solar insolation cycles. These shallow, rounded depressions—first identified by Mars Global Surveyor in 1999 and later monitored by the Mars Reconnaissance Orbiter (MRO)—have been observed to increase in size over time. However, large-scale analysis of SCF formation and growth has been limited by the slow and labor-intensive nature of manual mapping techniques. This study applies object-based image analysis (OBIA) to automate the detection and measurement of SCFs using High-Resolution …


Onset Of The Messinian Salinity Crisis: Insights From Molecular Organic Geochemistry, Albert Permanyer, Michael A. Kruge, Luis Gibert 2025 University of Barcelona

Onset Of The Messinian Salinity Crisis: Insights From Molecular Organic Geochemistry, Albert Permanyer, Michael A. Kruge, Luis Gibert

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The Messinian Salinity Crisis (MSC) generated extensive anoxic sediments under the evaporitic deposits in marginal Mediterranean basins. In an interdisciplinary approach combining field work with multiple laboratory techniques, the oil source rock potential and biomarkers of pre-evaporitic Messinian sediments from the Caltanissetta Basin (Sicily) were evaluated using Rock-Eval pyrolysis, gas chromatography-mass spectrometry, isotopic analysis and optical and electron microscopy. Organic-rich samples from the 45 m Serra Pirciata section consist of cycles of diatomaceous and carbonate layers alternating with organic shales of variable TOC. The organic matter is mostly optically amorphous, increasing in content upwards in the section. Of the 43 …


Groundwater In Nebraska, Troy E. Gilmore, Jesse T. Korus Dr. 2025 tgilmore10

Groundwater In Nebraska, Troy E. Gilmore, Jesse T. Korus Dr.

Conservation and Survey Division: Faculty and Staff Publications

What is groundwater? Groundwater is water that fills and moves between spaces in underground rocks, gravel, sand, or other materials.


Map Of The Thickness Of Ordovician Shales Across The Kentucky-Tennessee Mineral District (Ktmd), John B. Hickman, Alex M. Washburn, Georgina Lukoczki 2025 University of Kentucky

Map Of The Thickness Of Ordovician Shales Across The Kentucky-Tennessee Mineral District (Ktmd), John B. Hickman, Alex M. Washburn, Georgina Lukoczki

Research Data--KGS

The deposits of critical minerals have been found in metalliferous shales. To aid in critical mineral assessments of the Ordovician Shales in the Kentucky-Tennessee Mineral District (KTMD), this research project produced a map (digital GIS dataset) of the thickness (isopach) of the combined Upper Ordovician shale interval across the region. The subsurface input data are from oil/gas well records and exploratory mineral core. Well and core records for the KTMD were acquired from the state surveys of Tennessee and Kentucky. Along with the GIS files, a summary table of the 594 well and core data points used to produce this …


Thickness Of Devonian Shale, Kentucky-Tennessee Mineral District (Ktmd), John B. Hickman, Alex M. Washburn, Georgina Lukoczki 2025 University of Kentucky

Thickness Of Devonian Shale, Kentucky-Tennessee Mineral District (Ktmd), John B. Hickman, Alex M. Washburn, Georgina Lukoczki

Research Data--KGS

The deposits of critical minerals have been found in metalliferous shales. To aid in critical mineral assessments of the Devonian Shales in the Kentucky-Tennessee Mineral District (KTMD), this research project produced a map (digital GIS dataset) of the thickness (isopach) of the combined New Albany Shale/Chattanooga Shale/Ohio Shale interval across the region. The subsurface input data are from oil/gas well records and exploratory mineral core. Well and core records for the KTMD were acquired from the state surveys of Tennessee and Kentucky. Along with the GIS files, a summary table of the 6,607 well and core data points used to …


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