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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 …


The Relationship Between Lineaments And Cave Passages In Unfaulted Gently-Folded Strata, Snail Shell Cave, Central Tennessee, Usa, Mark Abolins, Joseph Firkaly-Paciera, Blake King, Cris Ocasio-Valentin, Jackson Slighter, Teagan Sullivan, Justin Whited Nov 2025

The Relationship Between Lineaments And Cave Passages In Unfaulted Gently-Folded Strata, Snail Shell Cave, Central Tennessee, Usa, Mark Abolins, Joseph Firkaly-Paciera, Blake King, Cris Ocasio-Valentin, Jackson Slighter, Teagan Sullivan, Justin Whited

International Journal of Speleology

Near Snail Shell Cave in central Tennessee, USA, seven image interpreters independently mapped lineaments using a 3DEP LiDAR DTM, revealing geomorphic and structural differences in and near different parts of the cave. MANOVA comparison of lineament and cave passage trend for Western, Central, and Eastern Snail Shell caves reveals statistically significant differences (p <0.05). The Western cave (mean depth 44 m) is in the gently-dipping limb of the Snail Shell anticline, and the Central cave (mean depth 31 m) is in the anticline hinge. In contrast, many Eastern cave passages (mean depth 40 m) cut across the anticline hinge and part of the limb of the Overall syncline. For both the Western and Central caves, a post-hoc Tukey’s HSD test fails to show that lineament trend within 235 m of the cave differs significantly from passage trend, and the test fails to show that the two differ significantly within 235 and 433 m of the Eastern cave. Additional statistical testing fails to show a difference between Western passage trend and bed strike, indicating the likelihood that lineaments and passages developed within strike-joints. However, testing shows a statistically significant difference between passage trend and bed strike for the Central and Eastern caves. The strike of joints inside the Eastern cave shows that it is within a joint zone which penetrates to depths of at least 80 m and is expressed at the surface as an ~4.2 km-long belt of elevated lineament line density. The lack of a statistically significant difference between Eastern passage trend and the trend of a nearby topographic escarpment suggests that many joints are stress release fractures formed during relatively recent erosion. For the Eastern cave, intersections between lineaments and structures would be attractive targets for groundwater exploration at depths typical of wells in carbonates.


Characterization Of River Discharge And Interaction With Shallow Groundwater Aquifers Along The Wabash River Using Seismological Methods, Jessica M. Cyr, Xiaotao Yang, Marty D. Frisbee Nov 2025

Characterization Of River Discharge And Interaction With Shallow Groundwater Aquifers Along The Wabash River Using Seismological Methods, Jessica M. Cyr, Xiaotao Yang, Marty D. Frisbee

Discovery Undergraduate Interdisciplinary Research Internship

The interaction between shallow aquifers and local rivers in the West Lafayette, Indiana area remains poorly understood. While surface water levels in the Wabash River and its tributaries are monitored at several USGS stream gauges, groundwater fluctuations are less well documented. Methods using seismic recordings, sensitive to subtle ground vibrations and subsurface structure, provide an alternative to characterize groundwater levels and river discharge. This project analyzes the temporal variations of ambient noise seismic data, examining the relationship to USGS river discharge, precipitation records, and other environmental factors. We currently focus on 1) changes in maximum amplitudes and peak frequencies within …


Formation And Extent Of The Cretaceous West Mountains Plutonic Complex, Ellen M. Nelson, Claire E. Ruggles, Basil Tikoff, Mollie Patzke, Kathleen D. Surpless, Jeffrey Vervoort, Richard Gaschnig Nov 2025

Formation And Extent Of The Cretaceous West Mountains Plutonic Complex, Ellen M. Nelson, Claire E. Ruggles, Basil Tikoff, Mollie Patzke, Kathleen D. Surpless, Jeffrey Vervoort, Richard Gaschnig

Earth and Environmental Geosciences Faculty Research

The West Mountains plutonic complex is a series of intrusive bodies, presently located in Idaho, that formed during a continuous period of Early to mid-Cretaceous magmatism in the northwest North American Cordillera. Granitoids of the West Mountains plutonic complex were emplaced across the boundary between accreted terranes and Laurentia following the Jurassic accretion of the Blue Mountains Province. New U-Pb zircon crystallization dates from the West Mountains plutonic complex ranging from 130 to 109 Ma and new zircon εHf isotopic compositions ranging from +12.1 to +4.7 suggest the complex is older and compositionally distinct from the younger than 85 Ma …


Record Of The Late Jurassic Cordilleran Margin From Detrital Zircon Analysis Of The Galice And Mariposa Formations, California And Oregon, Kathleen D. Surpless, Calvin Barnes, Aaron Yoshinobu Nov 2025

Record Of The Late Jurassic Cordilleran Margin From Detrital Zircon Analysis Of The Galice And Mariposa Formations, California And Oregon, Kathleen D. Surpless, Calvin Barnes, Aaron Yoshinobu

Earth and Environmental Geosciences Faculty Research

Details of the Late Jurassic tectonic evolution of the North American continental margin remain controversial, but a clear understanding of Late Jurassic tectonics is essential for understanding subsequent terrane accretion and displacement. Upper Jurassic strata of the Galice Formation in the western Klamath Mountains province and the Mariposa Formation in the Western Sierra Nevada metamorphic province were deposited along the margin of North America during this critical time. The Galice and Mariposa Formations have long been correlated, and these strata are the youngest rocks deformed during Late Jurassic Nevadan deformation in Oregon and California. Published and new detrital zircon age …


Magnesium, Iron, And Calcium Isotope Signatures Of Chicxulub Impact Spherules: Isotopic Fingerprint Of The Projectile And Plume Thermodynamics, Courtney Jean Rundhaug, Martin Schiller, Martin Bizzarro, Zhengbin Deng, Hermann D. Bermúdez Nov 2025

Magnesium, Iron, And Calcium Isotope Signatures Of Chicxulub Impact Spherules: Isotopic Fingerprint Of The Projectile And Plume Thermodynamics, Courtney Jean Rundhaug, Martin Schiller, Martin Bizzarro, Zhengbin Deng, Hermann D. Bermúdez

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The Cretaceous-Paleogene boundary (KPB) represents a massive extinction event in Earth's history, probably triggered by the Chicxulub asteroid impact ∼66 Ma. The event dispersed vast volumes of ejecta materials including exceptionally preserved impact spherules in the Gorgonilla Island KPB section. Previous work identified three populations of spherules at Gorgonilla: 1) ballistically transported molten spherules, 2) a mixture of molten and condensed spherules dispersed by the expansion of a high-temperature, turbulent cloud (the "pyrocloud"), and 3) tiny droplets condensed from the plume (the "fireball layer"). We determine the Mg, Fe, and Ca isotopic compositions of pristine spherules to better understand the …


Source Apportionment And Potential Health Risks Of Trace Metals In A Contaminated Urban River In New York/New Jersey Harbor System, Md Shahnul Islam, Sana Mirza, Huan Feng, Tapos Kumar Chakraborty, Yu Qian, Shinjae Yoo Nov 2025

Source Apportionment And Potential Health Risks Of Trace Metals In A Contaminated Urban River In New York/New Jersey Harbor System, Md Shahnul Islam, Sana Mirza, Huan Feng, Tapos Kumar Chakraborty, Yu Qian, Shinjae Yoo

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The Lower Passaic River (LPR), located within the New York/New Jersey Harbor Estuarine System, has experienced long-term industrial activities, resulting in elevated concentrations of trace metals in sediment and water. This study aims to assess the bioaccumulation behavior, potential human health risks, and sources of copper (Cu), lead (Pb), and mercury (Hg) in the LPR. Trace metal concentrations were measured in water, sediment, and seven edible aquatic species. Data were analyzed using statistical approaches, and evaluated by bioaccumulation factors (BAFs) and human health risk assessments based on U.S. Environmental Protection Agency (USEPA) guidelines. Results showed that Hg exhibited the highest …


Playa Sediment Bioaccessibility Presents Previously Unknown Risks To Population Health In A Water-Stressed Region Undergoing Lake Desiccation: Salton Sea, Usa, Jordan Jaeger Nov 2025

Playa Sediment Bioaccessibility Presents Previously Unknown Risks To Population Health In A Water-Stressed Region Undergoing Lake Desiccation: Salton Sea, Usa, Jordan Jaeger

Theses

Globally, drylands are expanding, and endorheic basins are in rapid decline. Saline lake desiccation exposes lakebed playa likely to become dust, posing potential health risks to surrounding communities. Studies investigating health risks from playa dust exposure often focus on health effects associated with the presence of airborne particulates, but fewer studies investigate health risks associated with dust source chemistry. This study examines dust source particle composition in a desiccating inland sea in a water-stressed agricultural region of California. Specifically, chemical bioaccessibility of bound trace elements uncovers risks to children, adults, and agricultural worker health. Arsenic exposure via sediment ingestion poses …


Spatially Mapped Statewide Estimated Potential Evapotranspiration Using An Efficient Surface Interpolation Method: A Case Study Of South Carolina, Sudhanshu S. Panda, Devendra M. Amatya, Ka Kit Liu, Augustine Muwamba, Timothy J. Callahan Nov 2025

Spatially Mapped Statewide Estimated Potential Evapotranspiration Using An Efficient Surface Interpolation Method: A Case Study Of South Carolina, Sudhanshu S. Panda, Devendra M. Amatya, Ka Kit Liu, Augustine Muwamba, Timothy J. Callahan

Journal of South Carolina Water Resources

Potential evapotranspiration (PET) exhibits substantial spatial and temporal variability across large landscapes, necessitating site-specific estimation for accurate environmental and water resource assessments. However, obtaining PET or ET data for specific locations across an entire state remains challenging due to the limited number of weather stations and associated environmental datasets. This study aimed to develop an automated geospatial modeling framework to map PET distribution across South Carolina, USA, using PET estimated by the temperature-based Hargreaves–Samani (H–S) method with daily weather data from 59 NOAA stations. Because the accuracy of spatial interpolation depends on both the target variable and the desired spatial …


Locations Of Outfalls In The Indian River Lagoon And Lake Worth Lagoon, Florida, Kelly M. Kibler, Melinda J. Donnelly, Vincent Encomio, Madison Giuntoli, Manisha Thenuwara, Brice Bennett, Laura Andrade Barron, Mariam Sonbol, Wynter Raine Seppala, Namritha Ramakrishnan, Jennifer Jordan Báez, Beth Orlando, Irene Arpayoglou, Melissa Meisenburg Nov 2025

Locations Of Outfalls In The Indian River Lagoon And Lake Worth Lagoon, Florida, Kelly M. Kibler, Melinda J. Donnelly, Vincent Encomio, Madison Giuntoli, Manisha Thenuwara, Brice Bennett, Laura Andrade Barron, Mariam Sonbol, Wynter Raine Seppala, Namritha Ramakrishnan, Jennifer Jordan Báez, Beth Orlando, Irene Arpayoglou, Melissa Meisenburg

Indian River Lagoon Shorelines

The spatial dataset: UCF_Outfalls_IRL_LWL.shp was created under grants from the Indian River Lagoon National Estuaries Program and Florida Sea Grant. These projects cumulatively led to creation of a living shoreline restoration prioritization model and hydrodynamic habitat suitability models for 1,550 km (963 miles) of estuarine shorelines in Indian River Lagoon (IRL) and Lake Worth Lagoon (LWL).

The dataset presented here includes the location of outfalls identified throughout the study region and general characteristics of the shoreline where they were identified.


Seagrass Persistence In The Indian River Lagoon And Lake Worth Lagoon, Florida, Kelly Kibler, Melinda Donnelly, Vincent Encomio, Madison Giuntoli, Manisha Thenuwara, Brice Bennett, Laura Andrade Barron, Mariam Sonbol, Wynter Raine Seppala, Namritha Ramakrishnan, Jennifer Jordan Báez, Beth Orlando, Irene Arpayoglou, Melissa Meisenburg Nov 2025

Seagrass Persistence In The Indian River Lagoon And Lake Worth Lagoon, Florida, Kelly Kibler, Melinda Donnelly, Vincent Encomio, Madison Giuntoli, Manisha Thenuwara, Brice Bennett, Laura Andrade Barron, Mariam Sonbol, Wynter Raine Seppala, Namritha Ramakrishnan, Jennifer Jordan Báez, Beth Orlando, Irene Arpayoglou, Melissa Meisenburg

Indian River Lagoon Shorelines

The spatial dataset: UCF_seagrasspersistence_IRL_LWL.shp was created with support from the Indian River Lagoon National Estuaries Program and Florida Sea Grant. These projects cumulatively led to creation of a living shoreline restoration prioritization model and hydrodynamic habitat suitability models for 1,550 km (963 miles) of estuarine shorelines in Indian River Lagoon (IRL) and Lake Worth Lagoon (LWL). The dataset presented herein represents persistence of seagrass throughout waters of the IRL and LWL.


New Evidence Of Mid-Pleistocene Glaciations In The French Jura Mountains Using Debris Flow Deposits And U/Th Dating Of Speleothems (Verneau Karst Network), Margot Vivier, Stéphane Jaillet, Eglantine Husson, Edwige Pons Branchu, Jean-Baptiste Charlier Nov 2025

New Evidence Of Mid-Pleistocene Glaciations In The French Jura Mountains Using Debris Flow Deposits And U/Th Dating Of Speleothems (Verneau Karst Network), Margot Vivier, Stéphane Jaillet, Eglantine Husson, Edwige Pons Branchu, Jean-Baptiste Charlier

International Journal of Speleology

We redefine the extent of former glaciers in the northern Jura Mountains through the study of endokarst deposits. Sedimentary deposits (pebbly debris flows, laminated clays, and allochthonous limestone blocks) and chemical deposits (speleothems) were identified and studied using three complementary approaches: (i) detailed geomorphological mapping, (ii) petrographic analysis, and (iii) U/Th-dating. In addition, a surface geomorphological analysis made it possible to calculate the minimum erosion time required for the formation of the sinkhole linked to the underground study site. The study site is the Dolois Chamber, an underground site upstream of the Verneau karst network (Doubs Department, France). The combined …


Studies Of Seismicity In The Alaska Subduction Zone And Antarctica, Patrick Matulka Nov 2025

Studies Of Seismicity In The Alaska Subduction Zone And Antarctica, Patrick Matulka

Arts & Sciences Graduate Student Theses and Dissertations

This dissertation utilizes multiple methods of earthquake detection, relocation, and characterization to investigate the patterns of seismicity along the Alaska subduction zone and Antarctica. The studies of the Alaska subduction zone are built on the data collected during the Alaska Amphibious Community Seismic Experiment (AACSE) that deployed temporary land and ocean-bottom seismometers along the Alaska Peninsula and offshore regions from May 2018 to September 2019. Using seismic arrivals at those stations, as well as a combination of other land-based networks, I relocated 1307 earthquakes in the incoming plate and trench slope regions of the Alaska subduction zone with an absolute …


Shaping The Soil: A Comparison Of Equine, Bovine, And Ungrazed Hay Fields, Brody Ellis Higgs, Taylor Madison Wynn, Scottie Craig Berry Nov 2025

Shaping The Soil: A Comparison Of Equine, Bovine, And Ungrazed Hay Fields, Brody Ellis Higgs, Taylor Madison Wynn, Scottie Craig Berry

Scholars Week

Shaping the Soil: A Comparison of Equine, Bovine, and Ungrazed Hay Fields

Brody Higgs, Taylor Wynn, and Scottie Berry

Mentor: Dr. Iin. P. Handayani, PhD.

Hutson School of Agriculture, Murray State University, Murray, Kentucky, USA

ABSTRACT

Kentucky raises grazing species for multiple reasons, including food, recreation, and show. The most common of them are equine and bovine. These animals graze many acres across the state of Kentucky and impact soil properties in their pastures. This study was conducted on three pasturelands across Caldwell and Calloway counties in Kentucky. The pastures consisted of a cow pasture, a horse pasture, and a …


Uas Vs. In-Situ Measurement Techniques For Stream Substrates, Nathan Watson Nov 2025

Uas Vs. In-Situ Measurement Techniques For Stream Substrates, Nathan Watson

Scholars Week

UAS vs. In-situ Measurement Techniques for Stream Substrates

Key words: Geomorphic, Fluvial, ArcGIS Pro, UAS

Traditionally, geomorphic assessments of streams and fluvial structures have been conducted using in-situ field techniques. These techniques include taking Wolman (D50) pebble counts to characterize substrate, measurements of stream dimensions with tape, meter sticks, and Jacob staff. We studied the efficacy of using an uncrewed aerial system (UAS) to measure the substrate composition of a section of stream along the east fork of the Clarks River in Calloway County, Kentucky. The section consists of a 30-meter riffle-pool-run sequence, with variation in substrate size to test …


Exploiting Chloride Conservative Tendencies As Contaminant Surrogates In Groundwater Transport Modeling In A Typical Hydrogeological Environment Of Northern New Jersey, Toritseju Oyen, Duke Ophori Nov 2025

Exploiting Chloride Conservative Tendencies As Contaminant Surrogates In Groundwater Transport Modeling In A Typical Hydrogeological Environment Of Northern New Jersey, Toritseju Oyen, Duke Ophori

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

This study investigates the transport of chloride, a conservative tracer and surrogate for contaminants, in the fractured Brunswick aquifer of northern New Jersey using a dual-porosity MODFLOW-MT3DMS model. Focusing on the First Watchung Mountain region—a microcosm of northern New Jersey’s hydrogeological environment encompassing Montclair State University and adjoining communities, the numerical model simulates groundwater flow and solute transport in a hydrogeologically complex, urbanized setting. Results indicate that chloride migrates through the fractured aquifer via both local flow systems (e.g., Third River) and regional flow systems (Passaic River) within decades. Chloride concentrations exceeded the EPA’s 250 mg/L threshold much faster in …


Advancing Environmental Monitoring At Verde River Headwaters State Park Through Integrated Remote Sensing Technologies, Ronny Schroeder, Noah Morales, Colton Weeks, Reiner Zimmermann, Erika Podest, Hank Vincent Nov 2025

Advancing Environmental Monitoring At Verde River Headwaters State Park Through Integrated Remote Sensing Technologies, Ronny Schroeder, Noah Morales, Colton Weeks, Reiner Zimmermann, Erika Podest, Hank Vincent

Sustainability Conference

The establishment of Verde River Headwaters State Park in Chino Valley, Arizona, marks a significant conservation milestone with the acquisition of 734 acres of the historic Del Rio Springs Ranch by the Trust for Public Land in March 2024. Now under the stewardship of Arizona State Parks & Trails (ASPT), this site encompasses Sullivan Lake, Del Rio Springs, critical riparian habitats, and historically significant landmarks including the 1863 Arizona territorial capital and 1920s Fred Harvey Farm structures. This initiative yields substantial benefits, including annual water savings within the Prescott Active Management Area, the extension of the Peavine National Recreation Trail, …


Impact Of Lignin Content On Decomposition Rates, Lindsey Powell, Olivia Fawkes, Moses Elijah Cadawas, Isaac Paul Dent, Darlene Panvini Nov 2025

Impact Of Lignin Content On Decomposition Rates, Lindsey Powell, Olivia Fawkes, Moses Elijah Cadawas, Isaac Paul Dent, Darlene Panvini

Science University Research Symposium (SURS)

This study aimed to analyze decomposition rates of plants containing different amounts of lignin. Lignin can be found within cell wall structures in plants and aids in natural rigidity. Opuntia humifusa was chosen to represent plants with high levels of lignin, and Allium schoenoprasum was chosen in contrast because of its significantly lower levels of lignin. Due to these characteristics, A. schoenoprasum is hypothesized to decompose at a quicker rate than O. humifusa. To test this hypothesis, eight samples of O. humifusa and eight samples of A. schoenoprasum were placed in litter bags to prevent macroorganisms from aiding in …


Living Shoreline Prioritization And Hydrodynamic Habitat Suitability Models For Restoration In The Indian River Lagoon And Lake Worth Lagoon, Florida, Kelly M. Kibler, Melinda J. Donnelly, Vincent Encomio, Madison Giuntoli, Manisha Thenuwara, Brice Bennett, Laura Andrade Barron, Mariam Sonbol, Wynter Raine Seppala, Namritha Ramakrishnan, Jennifer Jordan Báez, Beth Orlando, Irene Arpayoglou, Melissa Meisenburg Nov 2025

Living Shoreline Prioritization And Hydrodynamic Habitat Suitability Models For Restoration In The Indian River Lagoon And Lake Worth Lagoon, Florida, Kelly M. Kibler, Melinda J. Donnelly, Vincent Encomio, Madison Giuntoli, Manisha Thenuwara, Brice Bennett, Laura Andrade Barron, Mariam Sonbol, Wynter Raine Seppala, Namritha Ramakrishnan, Jennifer Jordan Báez, Beth Orlando, Irene Arpayoglou, Melissa Meisenburg

Indian River Lagoon Shorelines

The spatial dataset: UCF_shorelinemodel_IRL_LWL.shp, was created with support from the Indian River Lagoon National Estuaries Program and Florida Sea Grant. These projects cumulatively led to creation of a living shoreline restoration prioritization model and hydrodynamic habitat suitability models for 1,550 km (963 miles) of estuarine shorelines in Indian River Lagoon and Lake Worth Lagoon.

The dataset presented herein includes:

  1. shoreline data from >15,000 transects collected in the field,
  2. shoreline wave climate data created through hydrodynamic modeling and frequency analysis of historic data,
  3. categorization of potential risk for shoreline boat wake impact,
  4. persistence of seagrass within 210 m of the shoreline, …


Climatic Controls On Soil Production, Transport And Chemical Erosion: Insights From Modelling Topography, Soils And Cosmogenic Nuclides At Little Lake, Oregon, Miles M. Reed, Ken L. Ferrier, Jill A. Marshall, Josh J. Roering, J. Taylor Perron Nov 2025

Climatic Controls On Soil Production, Transport And Chemical Erosion: Insights From Modelling Topography, Soils And Cosmogenic Nuclides At Little Lake, Oregon, Miles M. Reed, Ken L. Ferrier, Jill A. Marshall, Josh J. Roering, J. Taylor Perron

Geology Faculty Publications and Presentations

Predicting physical and chemical erosion rate responses to climate change are an ongoing challenge in geomorphology. A promising approach for investigating this is by measuring transient variations in physical and chemical erosion rates during climatically variable time periods, which can be accomplished by measuring cosmogenic nuclide concentrations and chemical depletion in sedimentary deposits. Interpreting such measurements warrants applying landscape evolution models that track variations in topography, cosmogenic nuclide concentrations and chemical depletion in soils. We applied a recently developed model that tracks these quantities at Little Lake, Oregon. Previous studies documented variations in cosmogenic nuclide concentrations and chemical depletion in …


Stable Isotope Paleoecology In The Bridgerian (Early Eocene): Investigation Of The Bridgerian Crash And The Canopy Effect, Aaron M. English Nov 2025

Stable Isotope Paleoecology In The Bridgerian (Early Eocene): Investigation Of The Bridgerian Crash And The Canopy Effect, Aaron M. English

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

The Early Eocene Climatic Optimum (EECO) was the warmest sustained interval of the Cenozoic. Its waning stages coincided with a marked decline in mammalian biodiversity known as the Bridgerian Crash, which was likely driven by increasingly cooler and drier conditions. Paleobotanical evidence suggests the early Eocene supported wet, subtropical to tropical forests at mid-latitudes, however the structure of these forests at the close of the EECO remains poorly understood. In this study, I measure carbon isotope values (d13CE) from the enamel of early Bridgerian (~52.2 – 48.3 Ma) herbivorous mammals from the Greater Green River …


An Assessment Of The Impact Of Illegal Sand Mining On The Coastline Of Liberia, Alphena J. Logan Nov 2025

An Assessment Of The Impact Of Illegal Sand Mining On The Coastline Of Liberia, Alphena J. Logan

World Maritime University Dissertations

No abstract provided.


Flow Structure And Mixing Near A Small River Plume Front: Winyah Bay, Sc, Usa, Christopher Papageorgiou, George Voulgaris, Alexander E. Yankovsky, Diane Bennett Fribance Oct 2025

Flow Structure And Mixing Near A Small River Plume Front: Winyah Bay, Sc, Usa, Christopher Papageorgiou, George Voulgaris, Alexander E. Yankovsky, Diane Bennett Fribance

Faculty Publications

This study presents Eulerian data from Winyah Bay, SC, USA collected during the passage of a tidal plume. The data captured the evolution and structure of the plume and include high-resolution velocity and temperature time series, supplemented by temperature – salinity profiles from a MicroCTD profiler. The observations identified a pre-existing plume extending to 4 m, with a water density of 1023.6 kg m−3, laying above denser ambient waters. Upon arrival, the newly discharged tidal plume introduced a fresher layer (1020.7 kg m−3) extending to 2.6 m, gradually thinning due to radial spreading. The plume's frontal …


Protocol For Assessing And Managing Radon Gas Exposure Risks In Caves: A Case Study Of Altamira And Paleolithic Cave Art Of Northern Spain World Heritage Site, Sergio Sanchez-Moral, Javier Lario, Soledad Cuezva, Juan Carlos Cañaveras, Tamara Martín-Pozas, Angel Fernández-Cortés Oct 2025

Protocol For Assessing And Managing Radon Gas Exposure Risks In Caves: A Case Study Of Altamira And Paleolithic Cave Art Of Northern Spain World Heritage Site, Sergio Sanchez-Moral, Javier Lario, Soledad Cuezva, Juan Carlos Cañaveras, Tamara Martín-Pozas, Angel Fernández-Cortés

International Journal of Speleology

Exposure to radon and its progeny poses a significant health risk for workers in tourist caves. Implementing protective measures is challenging due to increasingly strict gas concentration and dose limits in new regulations. This study evaluates the annual effective radiation doses received by workers and researchers, considering seasonal and spatial radon variability. Radon levels, temperature, and ventilation patterns were continuously monitored for at least one year in each cave. Results show significant radon fluctuations influenced by seasonal ventilation regimes driven by thermal gradients between the cave and external atmosphere. Using International Commission on Radiological Protection guidelines, the study calculates the …


Risk Prediction Of Surface-Water Bursting In The Gully-Crossing Mining Section Of Shallow Coal Seams Within Thin Bedrock Zones, Niu Chao, Luo Yutao, Liu Ning, Xiao Lele, Sun Qiang, Zhang Weiwei, Xue Xicheng, Zeng Dabao, Bai Yang Oct 2025

Risk Prediction Of Surface-Water Bursting In The Gully-Crossing Mining Section Of Shallow Coal Seams Within Thin Bedrock Zones, Niu Chao, Luo Yutao, Liu Ning, Xiao Lele, Sun Qiang, Zhang Weiwei, Xue Xicheng, Zeng Dabao, Bai Yang

Coal Geology & Exploration

Background The gully-crossing mining of shallow coal seams within thin bedrock zones is prone to connecting hydraulically conductive fracture zones in the overburden with surface water bodies, significantly increasing the risk of water disasters, such as water inrushes and surface-water bursting in mines. Some mining faces in the Shandong Coal Mine, Shaanxi Province are located beneath the Shajie Gully basin, where storm runoff is highly likely to flow into the underground mine through mining-induced fractures, posing a serious threat to mine safety. Therefore, there is an urgent need to research risk identification and assessment of surface-water bursting. Methods This study …


Influence Patterns Of Nanomaterials On The Properties Of Ultrafine Sulfoaluminate Cement, Li Xiaolin, Wang Pengfei, Gao Yinghui, Zhang Mingxuan, Dong Enyuan, Qu Yue, Zhao Yue Oct 2025

Influence Patterns Of Nanomaterials On The Properties Of Ultrafine Sulfoaluminate Cement, Li Xiaolin, Wang Pengfei, Gao Yinghui, Zhang Mingxuan, Dong Enyuan, Qu Yue, Zhao Yue

Coal Geology & Exploration

Objective and Methods This study aims to reduce the economic cost of sulfoaluminate cement-based grouting materials while also achieving excellent grouting reinforcement effects. To this end, it investigated the variation patterns of the compressive strength, setting time, and fluidity of the ultrafine fly ash (UFA)-ultrafine sulfoaluminate cement (USC) system by incorporating different dosages of silica fume (SF) and nano-silica (NS). Furthermore, the mechanisms behind the hydration reactions of the system were explored. Using multiple distinct testing techniques such as X-ray diffraction (XRD) mineralogy, Fourier transform infrared spectroscopy (FTIR), thermogravimetric-differential thermal analysis (TG-DTA), and scanning electron microscopy (SEM), this study analyzed …


Structural Characteristics Of The Overburden And Water Yield Property Of Weathered Bedrock Aquifer In A Representative Medium-Deep Coal Seam, Wang Lu, Hua Zhaolai, Huang Hao, Li Zenglin, Ren Shuaifeng, Wang Sitong Oct 2025

Structural Characteristics Of The Overburden And Water Yield Property Of Weathered Bedrock Aquifer In A Representative Medium-Deep Coal Seam, Wang Lu, Hua Zhaolai, Huang Hao, Li Zenglin, Ren Shuaifeng, Wang Sitong

Coal Geology & Exploration

Background The weathered bedrock aquifer represents a major water-filled aquifer encountered during coal mining in the Jurassic coalfield in northern Shaanxi Province. Therefore, evaluating the water yield property of the weathered bedrock aquifer is the key to the prevention and control of water hazards in coal seam roofs. Methods This study investigated panel 12 of the Caojiatan Coal Mine, Shaanxi Province. Analysis of the stratigraphic and lithological structure types of the overburden of coal seam 2–2 identified the weathered bedrock as the primary overlying water-bearing aquifer of the coal seam. Using net-to-gross (NTG) ratio, sandstone thickness, weathering influence index, …


An Experimental Study On The Breakthrough Pressure Of Different Co2 Phases Against Cap Rocks For Carbon Storage In Saline Aquifers, Dan Wendong, Li Yi, Wang Fugang, Hu Zhikai, Diao Yujie, Ma Xin, Liu Ting Oct 2025

An Experimental Study On The Breakthrough Pressure Of Different Co2 Phases Against Cap Rocks For Carbon Storage In Saline Aquifers, Dan Wendong, Li Yi, Wang Fugang, Hu Zhikai, Diao Yujie, Ma Xin, Liu Ting

Coal Geology & Exploration

Objective CO2 breakthrough pressure, a core parameter for characterizing the sealing performance of saline aquifers as cap rocks, holds important scientific significance and application value for ensuring the safety of CO2 geological storage engineering and assessing its storage potential. However, there is a lack of systematic studies on the variation patterns and mechanisms of breakthrough pressure under different occurrence phases of CO2 (supercritical, liquid, and gaseous) currently. Accordingly, universal and reliable conclusions are yet to be reached. Methods This study conducted experiments on a natural low-permeability unsaturated sandstone core. Using the step-by-step method, 13 groups of breakthrough …


Characteristics And Driving Forces Of The Spatiotemporal Evolution Of Surface Water Bodies In Ecologically Fragile Mining Areas In The Yellow River Basin: A Case Study Of The Yushenfu Mining Area, Chen Chao, Xuan Ang, Hu Zhenqi, Wang Yiming, Zhang Jiachao, Wang Guo, Yang Fuqin Oct 2025

Characteristics And Driving Forces Of The Spatiotemporal Evolution Of Surface Water Bodies In Ecologically Fragile Mining Areas In The Yellow River Basin: A Case Study Of The Yushenfu Mining Area, Chen Chao, Xuan Ang, Hu Zhenqi, Wang Yiming, Zhang Jiachao, Wang Guo, Yang Fuqin

Coal Geology & Exploration

Background This study aims to respond to the strategic demand for ecological protection and high-quality development in the Yellow River basin. To this end, research on the characteristics and driving forces of the spatiotemporal evolution of surface water bodies under the disturbance of intensive coal mining serves as the basis and a prerequisite for mitigating the contradiction between coal mining and water resources in ecologically fragile mining areas of the Yellow River basin. Methods Based on 10 stages of remote sensing image data from 1980 to 2023, information about surface water bodies in the Yushenfu mining area was extracted using …


Compressive Deformations And Energy Dissipation Characteristics Of Broken Rock Masses Under Lateral Confinement, Tian Yu, Lin Haifei, Li Shugang, Shuang Haiqing, Xu Peiyun, Liu Sibo, Ji Pengfei, Cui Mingwei Oct 2025

Compressive Deformations And Energy Dissipation Characteristics Of Broken Rock Masses Under Lateral Confinement, Tian Yu, Lin Haifei, Li Shugang, Shuang Haiqing, Xu Peiyun, Liu Sibo, Ji Pengfei, Cui Mingwei

Coal Geology & Exploration

Objective This study aims to investigate the deformation and energy dissipation characteristics of broken rock masses in the caving zones of goafs during compression and to reveal their impacts on the movement and failure of overlying strata and surface subsidence. Using a self-developed experimental system, this study conducted compression experiments on broken rock masses under lateral confinement under different Talbot index values and axial stresses. Then, it analyzed variations in axial displacement, void ratio, relative breakage index, fractal dimension, and strain energy density of the broken rock masses during compression. Accordingly, this study quantified variation patterns of strain energy density …