Geology Commons^™

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 …

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

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 …

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, …

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 …

Applied Machine Learning In Mineral Prospectivity Mapping In The South Pass-Granite Mountains Of Wyoming, Carl D. York

Graduate Theses/Dissertations

The South Pass-Granite Mountains, comprised of Archean to Tertiary rocks embedded with an Archean greenstone belt in Central Wyoming, have historically been mined for gold, iron, steel, and silver. Rare earth elements have been of increasing interest in the region and thus, several datasets have become available. Knowledge driven and data driven models are used in mineral prospectivity mapping with input data including geological mapping, geochemical data, geophysical (USGS Critical Mineral magnetic and gravity data), radiometric (U, Th, K) data and multispectral remote sensing data. Mineral prospectivity has seen a rapid improvement in recent years using advancements in machine learning …

Spatiotemporal Dynamics Of Mountain Front Recharge Flow Paths And Their Contribution To Alluvial Aquifer Water Supply, Mikaela Bollag-Miller

Graduate Student Theses, Dissertations, & Professional Papers

Mountain Front Recharge (MFR) is a critical recharge source for alluvial basin aquifers throughout the Intermountain West, yet the spatial and temporal dynamics of distinct recharge pathways remain poorly constrained. This study investigates the seasonal and spatial dynamics of MFR pathways and evaluates their impact on the Missoula Aquifer, a sole-source alluvial aquifer in western Montana, USA. MFR includes both surface-water inflows from mountain areas and Mountain Block Recharge (MBR), the groundwater contribution to the basin aquifer. A valley-scale water balance was employed to estimate first-order contributions and temporal fluctuations of MBR flow paths. A three-layer steady-state MODFLOW groundwater model …

Investigation Of Reey Concentrations In Argillaceous Rocks Associated With Coal Beds In Southwestern West Virginia, Alyssa Cameron Long

Theses, Dissertations and Capstones

Rare earth elements (REEs) and Yttrium are classified as “critical minerals” that are used in many industries and are typically extracted from carbonatites and related alkaline plutonic rocks. The limited availability of REE+Y requires finding alternate sources such as coal fly ash, tonstein, fireclays, and shales. This study investigates the potential enrichment of shales, fireclays, and siltstones interbedded with coal from southwestern WV in REEY, and the mechanisms of such enrichment. Using ICP-AES analysis of various rock types shows that shales, silty shales, and siderite nodules interbedded with Fire Clay and Chilton Coal beds in the Kanawha Formation record the …

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, …

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 …

Nonstationary Spatial Correlation Of Earthquake Ground Motions In California, Pengfei Wang, Busra Bocekli, Junhui Yang, Scott J. Brandenberg, Jonathan P. Stewart

Civil & Environmental Engineering Faculty Publications

Assessing seismic risk to spatially distributed infrastructure systems requires realistic representations of spatially correlated ground motions. Existing models for the spatial correlations of ground motions rely on strong second-order stationarity assumptions, under which the correlation structure is assumed to be invariant across space, potentially masking regional variations. Because repeatable site and path effects can vary spatially, the resulting correlation structure is likely to be nonstationary. We propose a nonstationary spatial correlation method that captures geographically varying correlation decay behavior. We compute site-to-site Pearson correlations of within-event residuals using earthquakes recorded at both sites in each site pair and model the …

Preliminary Analysis Of The Spatial Distribution Of Microplastics Along The Cuyahoga River, Northeast, Ohio, Ella Pitz

Williams Honors College, Honors Research Projects

Plastics are nearly ubiquitous throughout modern society, and when left in the natural environment, they degrade into microplastics. Microplastics are particles that range in diameter from 5 millimeters down to nanometers, and microplastics pose many potential environmental and health risks due to their small size and ease of ingestion. While the study of microplastics in the environment has become more common over the past ten years, microplastic concentrations remain unexplored in many regions throughout the country. Here I present a method for separating microplastics from organic matter and clastic sediment as well as preliminary measurements of microplastic concentrations in sediment …

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

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

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 …

Report 17—Revisions To The Articles Of Organization And Procedure Of The Commission On Stratigraphic Nomenclature Of The Americas, Lynn T. Dafoe, Robert B. Macnaughton, Marie-Perre Aubry, Carlton E. Brett, James R. Lehane, Fernando Núñez-Useche, Randall C. Orndorff, Frank Brunton, Lucy E. Edwards, Richard H. Fluegeman, Howard Harper, Robert Matthew Joeckel, Norman P. Lasca, B. H. Tew

Conservation and Survey Division: Faculty and Staff Publications

Several revisions to the Articles of Organization and Procedure for the North American Commission on Stratigraphic Nomenclature have been adopted following the 75th, 79th, and 80th annual meetings of the Commission in 2020, 2024 and 2025, respectively. Of these, the most substantial change was revision of Article III regarding membership composition of the Commission and the addition of new member organizations from Central and South America and the Caribbean region. As a result, the Commission also voted to change its name to be more inclusive of the expanding membership, with approval of the name: Commission on Stratigraphic Nomenclature of the …

Understanding How Erosion And Unit Thickness Alter The Deformation Of Fold-Thrust Belts, Kaitlyn E. Gallis, Caroline M. Burberry

Nebraska Academy of Sciences: Programs and Proceedings

When a collision of two tectonic plates occurs, fold thrust belts develop, which are widely recognized as the most common mode in which the crust accommodates shortening. Most analog models do not consider erosion when documenting fold thrust belt formation. The lack of experiments on this topic means there are limited consistent studies on the relationship between erosion and deformation. Preliminary experiments suggest that the typical forward breaking thrust sequence is altered by eroding the hinterland, something this experiment series aims to prove or disprove. The new contribution of this work is a systematic evaluation of the variation in initial …

A Geospatial Assessment Of Groundwater Salinization In A Multi-Aquifer System: Durango, Mexico, Juan Lopez-Sierra

Graduate Theses/Dissertations

Groundwater salinization poses a critical environmental concern for water resource sustainability in arid and semi-arid regions. This study evaluates spatial and temporal patterns of groundwater salinity across the state of Durango, Mexico, using total dissolved solids (TDS), sodium adsorption ratio (SAR), as salinity indicators and nitrate-nitrogen (NO₃–N) as an anthropogenic indicator. Groundwater quality data were obtained from (CONAGUA), a Mexican water agency. To assess salinity variations with respect to time, while minimizing interannual sampling bias, two multi-year sampling periods were selected: 2012-2013, and 2020-2021. Final datasets consisted of 122 wells for 2012–2013 and 131 wells for 2020–2021. The wells were …

Modeling The Effects Of Subsurface Tile Drainage On Atrazine And Nitrate Transport In Till Soils Of Iowa, Madison Hobbs

West Chester University Graduate Theses, Dissertations, and Final Projects

Tile drainage design influences groundwater flow pathways, residence time, and agrochemical transport in agricultural soils. This study evaluates how differences in drainage design affect subsurface flow behavior and contaminant transport in glacial till soils. A groundwater model was developed to compare conventional and controlled drainage systems with a shallow drainage system, and particle tracking was used to examine flow paths and residence times.

The results show that tile drainage creates distinct shallow and deeper flow pathways. In the conventional and controlled model, 88% of particles were captured by drains, while 12% reached the general head boundary. The shallow system drains …

Flood-Season Surface Water-Groundwater Interactions Across Distinct Geomorphic Units In A Yellow River Great Bend Tributary Basin, Yinlong Wang, Ruizhong Gao, Debin Jia, Xixi Wang, Tingxi Liu, Xiaomin Liu, Shiming Bai

Civil & Environmental Engineering Faculty Publications

Surface water-groundwater interactions are complex in the Great Bend region of the Yellow River. Clarifying water exchange and source differences among geomorphic units is important for understanding regional hydrological processes and improving water resources management. In this study, the Wulanmulun River Basin, a typical tributary of the Yellow River, was selected as the study area. A total of 90 water samples were collected, including 25 river water samples, 43 groundwater samples, and 22 precipitation samples. Gibbs diagrams, multivariate statistical analysis, PMF, and MixSIAR models were used to investigate the hydrochemical and isotopic characteristics, source contributions, and transformation relationships of surface …