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Last Glacial Maximum And Late Glacial Aeolian Sand Activity, South-Central Indiana, Usa, H. M. Loope, J. L. Antinao, P.R. Hanson, P. M. Jacobs, D. A. Grimley 2026 University of Nebraska - Lincoln

Last Glacial Maximum And Late Glacial Aeolian Sand Activity, South-Central Indiana, Usa, H. M. Loope, J. L. Antinao, P.R. Hanson, P. M. Jacobs, D. A. Grimley

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


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 2026 University of Nebraska - Lincoln

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 …


Integrated Seismic And Sequence Stratigraphic Analysis Of The Abu Madi Formation, Baltim Field, Nile Delta, Egypt, Nouran Mostafa Eissa, Mostafa Toni, Alhussein Adham Basheer, Amr Talaat, Amir Ismail 2026 Geology Department, Faculty of Science, Capital University, Cairo, Egypt

Integrated Seismic And Sequence Stratigraphic Analysis Of The Abu Madi Formation, Baltim Field, Nile Delta, Egypt, Nouran Mostafa Eissa, Mostafa Toni, Alhussein Adham Basheer, Amr Talaat, Amir Ismail

Trends in advanced sciences and technology

Despite the economic significance of the Messinian Abu Madi Formation as a primary gas reservoir target in the Nile Delta Basin, a high-resolution, field-scale integration of seismic sequence stratigraphy with quantitative petrophysical characterization remains lacking for the Baltim area. This study addresses this gap by presenting an integrated seismic sequence stratigraphic and petrophysical analysis of the Upper Miocene Abu Madi Formation within the prolific Baltim gas fields, offshore Nile Delta, Egypt. The objectives are to characterize its depositional architecture, delineate reservoir distribution, and assess hydrocarbon potential. The workflow synthesizes well log data from five key wells with a grid of …


Does The Powder River Pass Shear Zone Exist? Geologic Map And Geochronology Of The Bighorn Mountains Caribou Creek 7.5-Minute Quadrangle, Lula G. Staley 2026 Illinois State University

Does The Powder River Pass Shear Zone Exist? Geologic Map And Geochronology Of The Bighorn Mountains Caribou Creek 7.5-Minute Quadrangle, Lula G. Staley

Theses and Dissertations

This study produced a 1:24000-scale geologic map of the Caribou Creek 7.5-minute quadrangle in the Bighorn Mountains, Wyoming, by integrating field observation and U-Pb zircon age data. The results of this study will contribute to the USGS EDMAP program by subdividing the southern gneiss terrain. The quadrangle occurs almost entirely in the Bighorn National Forest and is in the drainage of Clear and Crazy Woman creeks. Elevations range from 6,800-9,400 ft. The quadrangle is dominated by Archean crystalline rocks of the Wyoming Province Beartooth-Bighorn Magmatic terrane, mainly granodiorite and tonalite gneiss with lesser migmatite. Several orientations and ages of mafic …


Investigating Phosphorus Load Trends And Driving Factors In Illinois Watersheds Using Machine Learning Algorithms, Hannah Lartey 2026 Illinois State University

Investigating Phosphorus Load Trends And Driving Factors In Illinois Watersheds Using Machine Learning Algorithms, Hannah Lartey

Theses and Dissertations

Phosphorus (P) pollution in Illinois watersheds has become a significant water quality concern. Recent studies have shown increasing concentrations in streams and rivers, leading to eutrophication, which damages aquatic ecosystems and threatens human health. This study examines temporal trends in total phosphorus loads across 79 monitoring stations in Illinois from 1979 to 2020 and identifies the main environmental factors that influence P load variability. Trend analyses were conducted using the nonparametric Mann-Kendall and Sen’s slope methods. GIS-based climate, hydrology, and soil property datasets were assembled for each monitoring station. These datasets were used to build machine learning models using the …


Milankovitch Paleoclimatic Signals In Upper Permian–Lower Triassic Fluvial-Lacustrine Records, Bogda Mountains, Greater Turpan-Junggar Intracontinental Rift Basin, Nw China, Wentao Zhang 2026 Missouri University of Science and Technology

Milankovitch Paleoclimatic Signals In Upper Permian–Lower Triassic Fluvial-Lacustrine Records, Bogda Mountains, Greater Turpan-Junggar Intracontinental Rift Basin, Nw China, Wentao Zhang

Doctoral Dissertations

"The objective of this study is to understand whether Milankovitch climatic and/or tectonic processes influenced the sedimentation of the upper Permian–Lower Triassic fluvial-lacustrine cyclic deposits in Bogda Mountains, greater Turpan-Junggar intracontinental rift basin, Xinjiang Uygur Autonomous Region, NW China. This study carried out gamma analysis, gamma and astronomical tuning, and spectral analysis on the Wutonggou, Jiucaiyuan, and Shaofanggou low-order cycles of the South and Central Taodonggou, South and North Tarlong, Dalongkou, and Zhaobishan sections. Stable and positive gamma values support the assumption of facies-dependent sedimentation rates for non-marine facies. The sedimentation rates range from 0.04 to 2.43 m/kyr, and 0.21 …


Innovative Methods In Intact Rock Deformation Detection, Ali Abdullah M Alzahrani 2026 Missouri University of Science and Technology

Innovative Methods In Intact Rock Deformation Detection, Ali Abdullah M Alzahrani

Doctoral Dissertations

"An accurate assessment of intact rock deformation is imperative in engineering activities carried out either in or above rock masses. However, instruments used for post-peak deformation are easily debonded and cannot record the whole process of post-peak deformation required in the failure modeling of rocks. This dissertation focuses on the investigation of the performance of two non-contact measuring systems (Laser Displacement Sensor (LDS) and Inductive Proximity Sensor (IPS)) compared to the contact type instrument (conventional Strain Gauge System (SGS)) in monitoring intact rock deformations. Subsequently, an IPS was installed in a high-pressure triaxial testing system before investigating its performance in …


The Nature And Origin Of The Strodes Creek Member Of The Lexington Limestone, Central Kentucky, Claire J. Mendenhall 2026 University of Kentucky

The Nature And Origin Of The Strodes Creek Member Of The Lexington Limestone, Central Kentucky, Claire J. Mendenhall

University of Kentucky Master's Theses

The Strodes Creek Member of the Lexington Limestone is a small, unusual member that is largely known for its beds of fragmented and overturned stromatoporoids. The Strodes Creek Member occurs as two distinct stratigraphic bodies, wholly encompassed by the Millersburg Member, which represents a shallow, open-marine, mixed-clastic-carbonate platform, characterized by thin-bedded to nodular, fossiliferous calcarenites and calcirudites interbedded with shale. In contrast to the Millersburg, the Strodes Creek exhibits a lithologic background of dark, organic-rich, calcareous shales with a westward-thickening section of very irregularly bedded, stromatoporoid-rich, fossiliferous calcisiltites (packstones and wackestones). The calcisiltites are commonly associated with hummocky crossbedding, pinch-and-swell …


Spatiotemporal Dynamics Of Mountain Front Recharge Flow Paths And Their Contribution To Alluvial Aquifer Water Supply, Mikaela Bollag-Miller 2026 University of Montana, Missoula

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 …


Data Repository For The Distribution Of Small Impact Craters Along The Msl Curiosity Rover Traverse In Gale Crater, Mars, Megan E. Hoffman 2026 University of New Mexico

Data Repository For The Distribution Of Small Impact Craters Along The Msl Curiosity Rover Traverse In Gale Crater, Mars, Megan E. Hoffman

Earth and Planetary Sciences Faculty and Staff Publications

The theoretical limit of the smallest impact crater diameter that can form under current martian atmospheric conditions is approximately 0.25 m, which is near the projected pixel size of the best orbital imagers around Mars. As a result, there have been limited studies into how the retention of the smallest impact craters on Mars varies with surface properties, since orbital images alone cannot confidently resolve them. Rovers and landers are needed to confidently differentiate and measure these smallest craters. Here we catalog small impact craters seen along the first 25 km, or 3120 sols of the Mars Curiosity rover traverse …


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 2025 Faculty of Science, Charles University in Prague, Czech Republic

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 2025 Department of Geoscience, University of Dar es Salaam, P.O. Box 35052, Dar es Salaam, Tanzania.

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 2025 HUN-REN - MTM - ELTE Research Group for Paleontology, Hungary

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 2025 University of Nevada, Las Vegas

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 2025 Western Colorado University

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 …


Contemporary Martian Geomorphic Processes And The Suitability Characterization Of Terrestrial Analogues, Daniel Paul Mason 2025 University of New Mexico

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 …


Dense Temporary Array Investigation Of Jemez Uplift Seismicity, Jillian D. Podmore 2025 University of New Mexico

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 2025 Department of Earth and Planetary Sciences

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 …


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

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 2025 Utah State University

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.


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