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Constraining The Tectono-Climatic Evolution Of The Northern Rocky Mountains: Insights From Volcanic Glass, Leaf Water, And Leaf Wax Hydrogen Isotopes, Rijumon Nandy Jan 2026

Constraining The Tectono-Climatic Evolution Of The Northern Rocky Mountains: Insights From Volcanic Glass, Leaf Water, And Leaf Wax Hydrogen Isotopes, Rijumon Nandy

Earth & Environmental Sciences Dissertations

The Eocene-Oligocene period in the North American Cordillera represents a period of great intrigue with complex interactions among tectonics, climate, and surface processes. Although this period is generally associated with synorogenic extension associated with gravitational collapse of the Cordillera, the paleotopographic history remains debated. Existing studies offer conflicting interpretations, suggesting either sustained elevations or modest uplift during this time. Notably, recent reconstructions based on volcanic glass δD values have proposed renewed uplift during the early Oligocene, which needs to be tested with a more extensive and robust dataset. Concurrently, global cooling and aridification during this interval may have been amplified …


Understanding The Drivers Of Marine Sediment Diagenesis In Carbonate-Bearing Sediments, Alex Reis Jan 2026

Understanding The Drivers Of Marine Sediment Diagenesis In Carbonate-Bearing Sediments, Alex Reis

Theses and Dissertations--Earth and Environmental Sciences

Marine sediments serve as an important geochemical record used to study how the Earth’s climate and oceans have changed throughout geologic time. As such, it is critical to understand how these sediments can be altered following deposition on the seafloor. This dissertation targeted two key geochemical archives, carbonate and pyrite, to link changing burial conditions with the resulting marine sediment chemistry. In particular, primary carbonate minerals record several indicators of past ocean chemistry, while pyrite preserves information related to the redox state of the sediment during deposition and burial. Additionally, secondary processes associated with changes in pore fluid chemistry and …


Supplementary Material For Experimental Constraints On Rock And Mineral Alteration By Magmatic Gas: Implications For Mars (Safari Et Al., In Review), Natalie Zimmermann Jan 2026

Supplementary Material For Experimental Constraints On Rock And Mineral Alteration By Magmatic Gas: Implications For Mars (Safari Et Al., In Review), Natalie Zimmermann

Geosciences Research Data

This file contains supplemental data for the JGR manuscript Experimental Constraints on Rock and Mineral Alteration by Magmatic Gas: Implications for Mars (Safari et al., in review). It includes SEM images and associated EDS spectra of altered targets and phase coatings produced in gas-rock alteration experiments.


Non-Destructive Characterization Of Variously Colored Gypsum And Aragonite/Calcite Speleothems From The Cigalère Cave (Ariège, France), Martin Vlieghe, Johan Wouters, Gérald Fanuel, Jean-François Drion Du Chapois, Anne Gallez, Stéphane Pire-Stevenne, Gaëtan Rochez, Johan Yans Jan 2026

Non-Destructive Characterization Of Variously Colored Gypsum And Aragonite/Calcite Speleothems From The Cigalère Cave (Ariège, France), Martin Vlieghe, Johan Wouters, Gérald Fanuel, Jean-François Drion Du Chapois, Anne Gallez, Stéphane Pire-Stevenne, Gaëtan Rochez, Johan Yans

International Journal of Speleology

The Cigalère Cave is a 21 km-long karstic cave located in the Ariège Department, in the French Pyrenees, and underlies directly the Bentaillou Pb-Zn-Fe sulfide ores. The cave hosts abundant gypsum mineralizations, some of them exhibiting various colorations including blue, yellow, purple, orange and black. Due to strict preservation policies, these colored mineralizations have not been studied much. Here we propose a non-destructive characterization of five distinct gypsum or carbonate speleothem structures from the Cigalère, exhibiting different colorations. To comply with the preservation policies, no sample was taken from the cave, and all speleothems were analyzed in situ using portable …


Slip Kinematics And Structural Analysis Of The Keweenaw Fault System From Lake Linden To Hancock, Michigan, Katherine M. Langfield Jan 2026

Slip Kinematics And Structural Analysis Of The Keweenaw Fault System From Lake Linden To Hancock, Michigan, Katherine M. Langfield

Dissertations, Master's Theses and Master's Reports

The Keweenaw fault is a crustal-scale fault spatially associated with Mesoproterozoic rocks of the Midcontinent Rift System. Along the fault, older Portage Lake Volcanics have been thrust southeastward over younger Jacobsville sandstone. Ideas on the fault’s origin, from oldest to most recent, include that it is: (1) a reverse fault, (2) a normal fault formed during midcontinent rifting that was reactivated and inverted to a reverse fault during the Grenville orogeny, and (3) a detached thrust fault system initiated during the Grenville orogeny.

This thesis is based on a U.S. Geological Survey EdMap grant to remap a portion of the …


An Analysis Of Volcanic Lightning And Its Controlling Factors, Nathan Stamford Jan 2026

An Analysis Of Volcanic Lightning And Its Controlling Factors, Nathan Stamford

Honors Theses

Volcanic lightning, first documented during the 79 AD eruption of Mount Vesuvius, includes any electrical discharge that is generated during a volcanic eruption rather than a thunderstorm. By analyzing individual eruptions and performing laboratory experiments, previous research has identified multiple controlling factors that influence the charging mechanisms and generation of volcanic lightning. While the previous research has made significant discoveries about the phenomenon, the exact relationship between many of these controlling factors and volcanic lightning generation has been poorly quantified. In this study, we investigate these controlling factors and show that they have a wide range of influence over volcanic …


Hydrogeochemical And Redox Controls On Nitrate And Arsenic Co-Occurrence In The Western Kansas High Plains Aquifer (Usa): A Composite Health Risk Assessment And The Case For Risk-Informed Private Well Governance, Jonathan Kuffour Owusu Jan 2026

Hydrogeochemical And Redox Controls On Nitrate And Arsenic Co-Occurrence In The Western Kansas High Plains Aquifer (Usa): A Composite Health Risk Assessment And The Case For Risk-Informed Private Well Governance, Jonathan Kuffour Owusu

Master's Theses or Doctor of Nursing Practice

Fifty-one private domestic wells across western Kansas were sampled to quantify nitrate and arsenic occurrence, identify geochemical controls, and evaluate carcinogenic and non-carcinogenic health risks for adult and child receptors in a region where groundwater serves as the primary drinking water source with no routine regulatory oversight. Samples were analyzed for major ions, nutrients, and trace elements by ICP-MS, ion chromatography, and UV-Vis spectrophotometry. Shapiro-Wilk testing confirmed non-normal distributions for both contaminants; inter-county comparisons were therefore conducted using Kruskal-Wallis tests with Dunn's post-hoc correction. Health risk was quantified via chronic daily intake (CDI), hazard quotient (HQ), HQ-based Water Quality Index …


Paleo-Environmental Change In Deer Lagoon, Whidbey Island Interpreted From Diatoms And Lithology, Lourdes Garcia Jan 2026

Paleo-Environmental Change In Deer Lagoon, Whidbey Island Interpreted From Diatoms And Lithology, Lourdes Garcia

All Master's Theses

Puget Sound is a densely populated, tectonically active area that can be affected by earthquakes from local crustal faults and the Cascadia subduction zone capable of producing abrupt coseismic subsidence. Tidal wetlands are particularly sensitive to abrupt changes because they are depositional environments that reside at sea-level and their lithology and ecological communities are strongly controlled by elevation within the tidal frame. As a result, coseismic subsidence can disrupt established environmental gradients and leave distinguishable signatures preserved within the stratigraphy, like tidal mud directly over peat deposits. These preserved records provide an opportunity to reconstruct past earthquakes and associated relative …


The Geomorphology And Hydrogeology Of Pre-Restoration West Fork Teanaway River, Wa, Usa, Shana M. Egan Jan 2026

The Geomorphology And Hydrogeology Of Pre-Restoration West Fork Teanaway River, Wa, Usa, Shana M. Egan

All Master's Theses

The West Fork Teanaway (WFT) River in Kittitas County, WA is an entrenched bedrock river channel with disturbed floodplain geomorphology and degraded riparian ecology. Two stream restoration approaches, “stage 0” valley bottom reset and engineered logjam installation, will be installed at the WFT in summer 2026 by collaborators at the Washington State Department of Fish and Wildlife and Mid-Columbia Fisheries Enhancement Group. The objective of this study was to constrain the pre-restoration geomorphic and hydrologic conditions of the WFT. The WFT has an unconsolidated floodplain aquifer of predominantly coarse-grained fluvial deposits. Monitoring of groundwater and surface water levels began in …


Pre-Eruptive Timescales Via Olivine Diffusion Chronometry For Lava And Tephra Of The Schreibers Meadow Cinder Cone Eruption, Mount Baker (Kulshan), Wa, Sabrina Ansari Jan 2026

Pre-Eruptive Timescales Via Olivine Diffusion Chronometry For Lava And Tephra Of The Schreibers Meadow Cinder Cone Eruption, Mount Baker (Kulshan), Wa, Sabrina Ansari

All Master's Theses

Mount Baker is a very-high threat Cascade volcano and is located near densely populated areas in northern Washington, putting many at risk if an eruption were to occur. Schreibers Meadow cinder cone is located on the southern flank of Mount Baker and produced the Sulphur Creek (SC) tephra and lava 9.8 ka. Previous work on the SC eruption used petrology and geochemistry to reconstruct the pre-eruptive magmatic architecture beneath Mount Baker Volcanic Field, including olivine-hosted melt inclusions to determine crystallization pressures, as well as plagioclase- and clinopyroxene-derived diffusion timescales to determine magma storage timescales of several months and recharge-to-eruption timescales …


Tracking Co2 Illinois Ccs Monitoring Wells, University Of North Dakota. Energy And Environmental Research Center Jan 2026

Tracking Co2 Illinois Ccs Monitoring Wells, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about the Illinois carbon capture and storage (CCS) project. Includes information on the project's CO2 monitoring system.


Sedimentology, Paleontology, And Depositional Environments Of The Upper Devonian Lock Haven Formation In West Burlington Quarry, North-Central Pa, Michael Harman Jan 2026

Sedimentology, Paleontology, And Depositional Environments Of The Upper Devonian Lock Haven Formation In West Burlington Quarry, North-Central Pa, Michael Harman

Honors Theses

The Upper Devonian Lock Haven Formation in north-central Pennsylvania preserves evidence of significant climactic and evolutionary transitions, including the fin-to-limb transition and initial arborescence. The formation contains abundant sedimentary features, palynomorphs, trace fossils, and fish body fossils, making it crucial for reconstructing these paleoenvironments. However, integrated studies on the Lock Haven Formation are rare. This study characterizes the depositional environments, ichnology, paleontology, and age of the Lock Haven Formation. A recent exposure at the Insinger-Ward West Burlington Quarry reveals three middle to early late Famennian lithofacies associations (FAs). FA1 consists of red sandstone, shale, and mudstone containing rhizoliths (deeply penetrating …


Paleoflood Chronology For The West Branch Of The Susquehanna River Using Abandoned Chute Channel Sediments, Pennsylvania, Usa, Juliette A. Vanluven Jan 2026

Paleoflood Chronology For The West Branch Of The Susquehanna River Using Abandoned Chute Channel Sediments, Pennsylvania, Usa, Juliette A. Vanluven

Honors Theses

Anthropogenic climate change is altering the hydrologic cycle, increasing flood frequency and severity, with associated increased risks in population exposure. This is associated with increasing risks to the population of the Susquehanna River Valley, which supports over 600,000 people today. However, our understanding of the frequencies of large floods is limited by relatively short instrumental records. By studying sediments from an abandoned chute channel in the Robert Allen Natural Area near Williamsport, PA, we can extend the existing flood records using paleoflood slackwater sediments along the West Branch of the Susquehanna River.  Sylvan Dell is an abandoned chute channel that …


Deep Crustal Boundaries As Fluid Conduits: A Geochemical Investigation Of Mvt Mineralization In Kentucky And Beyond, Dairian Boddy M. Boddy Jan 2026

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 …


Using Grounded Iceberg Wake Patterns To Interpret Catastrophic Flood Events In Southcentral Alaska, Jana K. Macinnis Jan 2026

Using Grounded Iceberg Wake Patterns To Interpret Catastrophic Flood Events In Southcentral Alaska, Jana K. Macinnis

All Master's Theses

Catastrophic flood events such as landslide tsunamis and jökulhlaups in glaciated areas can transport and strand icebergs, which obstruct the flow of floodwaters and leave a unique and recognizable grounded iceberg wake pattern in the sediment surface. Grounded iceberg wake patterns (GIWs) were identified at the two study areas in Southcentral Alaska; the outwash plain of a 1967 landslide tsunami at the Grewingk Glacier and proglacial lake, and the Matanuska River valley which experienced an unrecorded jökulhlaup in recent geological times. From these sites, 110 GIWs were identified through visual interpretation of lidar imagery and characterized by measuring their geometry, …


An Introduction To Field Excursions For The 2026 Geological Society Of America Cordilleran Section Meeting In Loreto, Baja California Sur, México, Scott E.K. Bennett, Michael H. Darin, Genaro Martínez Gutiérrez Jan 2026

An Introduction To Field Excursions For The 2026 Geological Society Of America Cordilleran Section Meeting In Loreto, Baja California Sur, México, Scott E.K. Bennett, Michael H. Darin, Genaro Martínez Gutiérrez

Geology Faculty Publications and Presentations

The 122nd annual meeting of the Geological Society of America (GSA) Cordilleran Section will be held in Loreto, Baja California Sur, México, an idyllic and historic Sonoran Desert city nestled on the eastern shore of the Baja California peninsula. The 2026 Loreto meeting marks a milestone for GSA as it is the first time in the Section’s century-plus history that the meeting has been held on the Baja California peninsula and only the third time that the meeting has been held in México. Thus, the 2026 Loreto meeting and related field trips represent a meaningful expansion of the Section’s engagement …


Modeling The Development Of Keyhole Passage Morphology, Charlotte Boehme Jan 2026

Modeling The Development Of Keyhole Passage Morphology, Charlotte Boehme

2026 Research Poster Competition

Cave passage morphology is an important indicator of the hydrological conditions under which a cave passage was formed. Keyhole passages are a commonly occurring type of passage morphology that consists of a round, wide top with a smaller canyon incised in the bottom of the passage. These passages typically indicate a shift from fully water-filled to partially water-filled conditions. There are multiple mechanisms by which such a transition can occur, and little is understood about which of these mechanisms is most common, or whether aspects of keyhole passage morphology may indicate the primary formation mechanism. CaveCHAMP is a physically based …


Chronostratigraphy Using Stable Carbon Isotopes Of The Elliot Formation, South Africa, Aidan Del Pino Jan 2026

Chronostratigraphy Using Stable Carbon Isotopes Of The Elliot Formation, South Africa, Aidan Del Pino

2026 Research Poster Competition

The Elliot Formation in South Africa preserves a fossil-bearing record spanning the Late Triassic–Early Jurassic, a time marked by significant environmental changes related to the Central Atlantic Magmatic Province (CAMP) and the end-Triassic extinction event. Despite its importance, the Elliot Formation remains poorly constrained due to limited chronostratigraphic markers. Chronostratigraphy is the branch of geology that correlates and dates rock units in time, allowing researchers to arrange these rock units into a chronological sequence. Globally, the Triassic–Jurassic boundary is characterized by a pronounced negative carbon isotope excursion linked to CAMP volcanism and the end Triassic extinction event. This C-isotope excursion …


Origin Of The World-Class Eagle, Eagle East, And Tamarack Ni-Cu-Pge Deposits And Comparative Analysis With Other Midcontinent Rift- And Siberian Trap-Related Intrusions, Robert M. Nowak Jan 2026

Origin Of The World-Class Eagle, Eagle East, And Tamarack Ni-Cu-Pge Deposits And Comparative Analysis With Other Midcontinent Rift- And Siberian Trap-Related Intrusions, Robert M. Nowak

Dissertations, Master's Theses and Master's Reports

The 1.1 Ga Mesoproterozoic Midcontinent rift hosts the Eagle, Eagle East, and Tamarack Ni-Cu-PGE deposits and Embayment Prospect. These deposits are hosted by ultramafic igneous rocks and have some of the highest Ni-Cu grades on Earth. We use new bulk-rock data and published datasets (bulk-rock, mineral chemistry, and isotopic analyses) to examine major, minor, and trace element trends of both Midcontinent rift-related alkaline and tholeiitic intrusions. In addition, we compare the geochemical data to local kimberlite-hosted lower-crustal xenoliths and local igneous (Archean) and sedimentary (Paleoproterozoic) country rocks. We found the peridotite magma compositions dominantly consist of primitive mantle compositions with …


Assessing Glacial Mass Change And Its Impact On Water Resources In Parts Of The Himalayas Using Satellite Remote Sensing, Kriti Panta Jan 2026

Assessing Glacial Mass Change And Its Impact On Water Resources In Parts Of The Himalayas Using Satellite Remote Sensing, Kriti Panta

Theses and Dissertations

This study investigates long-term changes in terrestrial water storage and their impact on hydrological processes in glacier-fed regions of Nepal. The study focuses on the central to eastern Himalayan region, including major river basins within the Koshi system. Multiple datasets, including the Gravity Recovery and Climate Experiment (GRACE) and GRACE follow-on (GRACE-FO) missions satellite data, the Global Land Data Assimilation System (GLDAS) products, and in situ streamflow data, were used for the period 2002–2019. Terrestrial Water Storage Anomaly (TWSA) derived from GRACE data shows a strong decreasing trend over time, indicating significant water storage loss across the study area. Soil …


Workshop Outcomes Report: 2nd International Workshop On Seismic Resilience Of Arctic Infrastructure And Social Systems, Majid Ghayoomi, Daniela Morganti Jan 2026

Workshop Outcomes Report: 2nd International Workshop On Seismic Resilience Of Arctic Infrastructure And Social Systems, Majid Ghayoomi, Daniela Morganti

Faculty Publications

The report provides an overview of the second international workshop on Seismic Resilience of Arctic Infrastructure and Social Systems. The report discusses agenda, workshop activities, interdisciplinary working groups, and results. It ends with several strategic questions and investigation plans that were developed as part of the workshop activities.


Comparing Unet And Hrnet For Geomorphic Feature Extraction From Digital Terrain Model-Derived Land Surface Parameters, Behnam Solouki Jan 2026

Comparing Unet And Hrnet For Geomorphic Feature Extraction From Digital Terrain Model-Derived Land Surface Parameters, Behnam Solouki

Graduate Theses, Dissertations, and Problem Reports (ETD)

Automated extraction of geomorphic features from high spatial resolution terrain data is important for environmental monitoring, geohazard assessment, and landscape change analysis. This study compares two convolutional neural network architectures, UNet and High-Resolution Network (HRNet), for semantic segmentation of mine benches and sinkholes from lidar-derived digital terrain models and land surface parameters. Mine benches represent anthropogenic, elongated, stepped landforms associated with historic surface mining, whereas sinkholes are natural, compact depressions common in karst terrain. Three terrain-derived input layers were used: square-root-transformed slope, broad-scale topographic position index, and fine-scale annulus topographic position index. Models were trained using five training sample sizes, …


Deposition And Diagenesis Of Permo-Triassic Gypsum From Wyoming And Texas: Saline Lake And Groundwater Systems Of Equatorial Pangea, Maya Yamei Bradford Jan 2026

Deposition And Diagenesis Of Permo-Triassic Gypsum From Wyoming And Texas: Saline Lake And Groundwater Systems Of Equatorial Pangea, Maya Yamei Bradford

Graduate Theses, Dissertations, and Problem Reports (ETD)

Knowledge of gypsum textures and the processes that yield them is important for interpreting the history of environments, climates, and life on Earth. This is because gypsum textures are products of specific environmental, microbiological, and diagenetic processes, and because gypsum is relatively common in the Earth’s sedimentary record. Despite this significance, gypsum is relatively understudied. The fundamental goal of this dissertation is to advance our understanding of gypsum textures by presenting detailed, petrography-based investigations of Permo-Triassic gypsum from the continental interior of Pangea.

Gypsum is typical in the Permo-Triassic sedimentary record of tropical Pangea, where it is associated with red …


A New Parsimony-Based Method For Reconstructing Sequences Of Developmental Events And Estimating Rates Of Intraspecific Variation, With Applications To Trilobites, Alexander Benjamin Bradley Jan 2026

A New Parsimony-Based Method For Reconstructing Sequences Of Developmental Events And Estimating Rates Of Intraspecific Variation, With Applications To Trilobites, Alexander Benjamin Bradley

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ontogenetic Sequence Analysis (OSA) is a method for reconstructing multiple sequences of abrupt phenotypic transformations (developmental events) for sampled populations of any kind of organism. It makes use of cladistic parsimony software to produce a network, or graph, whose vertices represent unique phenotypes at different stages of maturity (“semaphoronts”) and whose edges describe the developmental events occurring between semaphoronts. It is a powerful tool for constraining the range of developmental variation possible for a given species and generating sample statistics capable of identifying both the most common and the outlier ontogenetic sequences. However, OSA has seen little use since its …


Geospatial Analysis Of Sinkhole Density And Characteristics In West Virginia, Marissa Shannon Loftus Jan 2026

Geospatial Analysis Of Sinkhole Density And Characteristics In West Virginia, Marissa Shannon Loftus

Graduate Theses, Dissertations, and Problem Reports (ETD)

Creation of a sinkhole map of West Virginia provides useful data to help identify areas susceptible to sinkhole related hazards, as well as allowing for detailed analysis of factors controlling karst development. Newly available, statewide LiDAR-derived digital elevation data have made mapping sinkholes over larger spatial extents feasible. For this study, sinkholes were mapped for all areas of West Virginia that are underlain by carbonate rocks; then the distribution and characteristics were evaluated overall and in four focus areas (Berkeley and Jefferson counties, Pendleton County, Greenbrier County, and Monroe County). These areas correspond to broader physiographic regions, with Berkeley, Jefferson, …


Evaluation Of Chromium-Crosslinked Amps-Hpam Copolymer Gels: Effects Of Key Parameters On Gelation Time And Strength, Maryam Sharifi Paroushi, Baojun Bai, Thomas P. Schuman, Yin Zhang, Mingzhen Wei Jan 2026

Evaluation Of Chromium-Crosslinked Amps-Hpam Copolymer Gels: Effects Of Key Parameters On Gelation Time And Strength, Maryam Sharifi Paroushi, Baojun Bai, Thomas P. Schuman, Yin Zhang, Mingzhen Wei

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Controlling CO2 channeling in heterogeneous reservoirs remains a major challenge for both enhanced oil recovery (EOR) and secure geological storage. AMPS-HPAM copolymers exhibit high-temperature resistance and brine tolerance compared with conventional HPAM gels, making them well suited for the harsh environments associated with CO2 injection. Chromium-based crosslinkers (CrAc and CrCl3) were investigated because sulfonic acid groups in AMPS can coordinate with trivalent chromium ions, enabling dual ionic crosslinking and the formation of a robust gel network. While organic crosslinked AMPS-HPAM gels have been widely studied, the behavior of chromium-crosslinked AMPS-containing systems, particularly their gelation kinetics under …


Effect Of Ionic Strength On Gelation Time And Strength Of Amps-Based Polymer Gels, Maryam Sharifi Paroushi, Xuyang Tian, Baojun Bai, Thomas P. Schuman, Yin Zhang, Mingzhen Wei Jan 2026

Effect Of Ionic Strength On Gelation Time And Strength Of Amps-Based Polymer Gels, Maryam Sharifi Paroushi, Xuyang Tian, Baojun Bai, Thomas P. Schuman, Yin Zhang, Mingzhen Wei

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Polymer gel treatment has been widely applied for improving sweep efficiency and controlling excessive water and gas production. Their performance depends on gelation time and final gel strength. In most studies, brine salinity is used to describe the effect of formation water on gel behavior. However, changing salinity also changes ionic strength and ion composition at the same time. Because of this coupling, it is difficult to identify the mechanisms controlling gelation, which has led to inconsistent trends in the literature. Increasing salinity has been reported to either slow or accelerate gelation and to weaken or strengthen gels depending on …


Empirical-Based Model Of Spatio-Temporal Errors, Godwin Naaba Ndaa Jan 2026

Empirical-Based Model Of Spatio-Temporal Errors, Godwin Naaba Ndaa

Masters Theses

This research develops an empirical model to characterize spatial-temporal InSAR errors and improve the accuracy of deformation time-series analysis. Using standardized Sentinel-1 HyP3 products and MintPy, the study quantifies how correlated noise affects velocity precision and validates the results against continuous GNSS velocities.

Residual velocities are near-Gaussian, with σ ~0.92–2.04 cm/yr and ~1 cm/yr on average. Variograms show power-law spatial structure with a non-zero nugget implicating troposphere and decorrelation while errors drop exponentially with more acquisitions; spatial uncertainty is strongly affected by unwrapping errors, coherence, and tropospheric noise, not simply troposphere.

A comparative assessment of on-demand cloud processing with other …


Data Repository For: Dorsey Et Al., 'Rapid Transient Uplift Driven By Active Slab Tear, Southern Calabria, Italy', Rebecca J. Dorsey, Nathan D. Brown, Sergio G. Longhitano, Marco Meschis, Domenico Chiarella, Charles P. Ogle Jan 2026

Data Repository For: Dorsey Et Al., 'Rapid Transient Uplift Driven By Active Slab Tear, Southern Calabria, Italy', Rebecca J. Dorsey, Nathan D. Brown, Sergio G. Longhitano, Marco Meschis, Domenico Chiarella, Charles P. Ogle

Earth & Environmental Sciences Datasets

Southern Italy preserves a well-studied record of deformation and uplift related to migrating oblique collision, trench retreat, and tearing of subducted ocean slabs. However, the surface expression of these processes is incompletely understood due to a lack of reliable ages for marine terraces >200 m above sea level (masl). Here we use luminescence methods to date shallow marine sands from terraces ~ 100 to 1,000 masl in southern Calabria and interpolate the results with regional surface mapping. Burial ages overlap across the full range of sampled elevations with a weighted mean of 118.8 ± 8.7 thousand years before present (ka). …


Evaluation Of A Novel Re-Crosslinkable Preformed Particle Gel For Conformance Control In Ultra-High Temperature Reservoirs, Yanbo Liu, Tao Song, Caleb Kwasi Darko, Thomas P. Schuman, Mingzhen Wei, Baojun Bai Jan 2026

Evaluation Of A Novel Re-Crosslinkable Preformed Particle Gel For Conformance Control In Ultra-High Temperature Reservoirs, Yanbo Liu, Tao Song, Caleb Kwasi Darko, Thomas P. Schuman, Mingzhen Wei, Baojun Bai

Chemistry Faculty Research & Creative Works

Preferential fluid flow remains a major challenge in subsurface energy production and gas storage operations, resulting in excessive water production in mature oil fields, reduced heat extraction in geothermal reservoirs, and low sweep and storage efficiency in CO2-EOR projects. Polymer gels are widely used to mitigate high-permeability channels; however, conventional systems exhibit limited plugging efficiency and short lifetimes in ultra-high-temperature reservoirs due to poor thermal stability. This study presents a novel ultra-high-temperature-resistant preformed particle gel (UHT-PPG) developed for conformance control in reservoirs with temperatures of 150–275 °C and severe super-K or channeling problems. The material was evaluated in …