Digital Commons Network^™

Geochronology Of Senèze, Eric Delson, Sébastien Nomade, Sevket Sen, Evelyne Debard, Jean-François Pastre, Jean-Jacques Bahain, Qingfeng Shao, Christophe Falguères

Publications and Research

The age of the Senèze mammalian fauna has been discussed since it was first reported in 1892. 40Ar/39Ar ages reported by Nomade et al. (2014) and recalculated here to agree with current standards placed the deposits between 2.20 and 2.07 Ma. Paleomagnetic data collected in 2001 and 2004 help to narrow the age range, especially of the levels yielding fossils in 2001–2006. In the western sector, fossils can be securely dated between 2.10 and 2.08 Ma, while in the southeastern sector, they are slightly older, between 2.20 and 2.18 Ma. Senèze is one of the few later Cenozoic European sites …

How The Biotic And Abiotic Factors In The Belle Forest Cave And Arboretum Soil Dictates Tree Species Prevalence, Amya A. Bingham

SPARK Symposium Presentations

A plethora of factors in the soil impact a plant’s health, including the presence of different biotic and abiotic factors. These include things like temperature, elevation, pH, microbial respiration and the presence of water, clay, loam, silt, sand, nitrogen, potassium, and phosphorus. Different soils will have varying amounts of these, which may dictate what is able to grow in them, and therefore also the surrounding area. This research project explores how the aforementioned biotic and abiotic factors affect the soil at the Belle Forest Cave and Arboretum. Three samples will be taken from four spots along a transect at this …

Innovative Soil Classification Approach For Achieving Global Biodiversity Framework Utilizing Integrated Data Fusion Of Emit And Multispectral Satellite Observations: Case Study Of Imam Turki Bin Abdullah Royal Reserve, Kingdom Of Saudi Arabia, Hesham Morgan, Ali Elgendy, Surendra Maharjan, Wenzhao Li, Tamer Ismail, Yehya Kh. Shehadeh, Ahmed Elgharib, Ahmed Abdullah Al-Dughairi, Ali El Muburak, Khaled Allam Harhash, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Soil classification is essential for sustainable land management, ecological conservation, and combating desertification, particularly in arid and semi-arid regions. This study integrates hyperspectral data from the Earth Surface Mineral Dust Source Investigation (EMIT) and multispectral imagery from Sentinel-2 to achieve accurate soil classification for the Imam Turki bin Abdullah Royal Reserve (ITBA) in Saudi Arabia. Using advanced Machine Learning (ML) techniques, including Extreme Gradient Boosting (XGBoost), the study highlights the power of data fusion in addressing the limitations of standalone remote sensing methods. The integration of hyperspectral and multispectral data combines the spectral richness of hyperspectral imaging with the spatial …

Equilibration Of Alluvial River Channel Geometry To Unsteady Boundary Conditions, Christian Erikson

Dartmouth College Ph.D Dissertations

The morphology of an alluvial river is the culmination of dynamic processes interacting across scales. When the boundary conditions of a fluvial system are modified, feedback effects among these processes reshape the channel by altering the flow of water and sediment. Environmental stressors, therefore, have the potential to propagate signals of change from watershed to grain scale features in a river channel. I trace the influence of modern climate change across these scales by first quantifying changes in the generation of surface runoff and sediment supply at watershed scales. I then identify how the subsequent changes in hydrological and sedimentological …

The Effects Of Snow Cover On The Dynamic Pressure Of Nuclear Detonation Blast Waves, Adam Card, Andrew W. Decker

Faculty Publications

Blast pressure is the primary military targeting metric for nuclear weapons. Any local conditions that affect blast pressure have the potential for altering nuclear plans, both from defensive and offensive standpoints. Understanding the impact of snow to the blast wave, therefore, provides a benefit both to military planners and to warfighters on the ground, for any operation occurring in arctic environments. No existing data provides a quantitative description of how snow on the ground affects a nuclear detonation blast wave passing over it. Similar blast waves passing over dust have experimentally proven to enhance blast pressure in a localized region.1 …

Biogenic Modification Of Tidally Modified Substrates From The Micro- To Macroscopic Scale, Rogers Clark Caldwell Buntin Ii

OES Theses and Dissertations

Digital outcrop models generated by high-resolution photogrammetric imagery permit investigations into organism-substrate interactions at the centimeter to sub-millimeter scale. This dissertation uses this three-dimensional technology to study two sedimentary successions— the Archaean Dresser Formation and Cretaceous Dakota Sandstone— by capturing images via unmanned aircraft systems and single lens reflex cameras. The ~3.48 Ga Dresser Formation provides evidence for some of the earliest life on Earth in the form of stromatolites and microbially induced sedimentary structures. Aerial imagery of the 3.5 km2 Buick Geoheritage reserve capture the site’s geologic structures and close-range imagery documents stromatolites and several microbially induced sedimentary structures …

College Of Natural Sciences Newsletter, Spring 2025, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Page 1 Dean's Message from Dr. Sen Subramanian
Page 2 Student Spotlights
Page 3 Kaushik honored, Three-Minute Thesis, & Ice Cores revealed
Page 4 Alumni Spotlight
Page 5 Day of Scholars
Page 6 Cyanide research, Record Research Expenditures, Adhikari awarded Miller Research Award
Page 8 Hanson Receives NSF Grant
Page 9 Snow Lab Research Team
Page 10 Faculty Awards
Page 11 Drone Day
Page 13 Khalaf Awarded Presidential Award

Detection Of Microplastics In The Hindgut Content Of Zophobasmoriolarvae, Zoey Drexler

Posters - 2025

Microplastic and nanoplastic pollution is a growing environmental concern, with potential impacts on soil ecosystems and the organisms within them. Insects play a crucial role in soil health, and their digestive processes may influence the fate of microplastics in terrestrial environments.

Detection of micro- and nano-plastic particles in complex mixtures such as soil, sediments, and feces is difficult because these small particles often resemble particles of mineral or organic materials. One way to visualize them more specifically is by using Nile Red, a stain which is a dull blue when in aqueous on hydrophilic conditions, but which fluoresces bright red …

Oxygen Depletion In Lake Waters May Skew Brgdgt‐ Inferred Temperatures By More Than 10°C, Jonathon H. Raberg, Gregory A. De Wet, Áslaug Geirsdóttir, Julio Sepúlveda, Gifford H. Miller

Geosciences: Faculty Publications

Abstract Branched glycerol dialkyl glycerol tetraether (brGDGT) paleothermometry is an important tool for paleoclimate research. Oxygen availability has been suggested to skew brGDGT‐inferred temperatures, but the effect is poorly constrained. Here, we examine the influence of dissolved oxygen (DO) on brGDGTs in lacustrine water filtrates. By examini10.1029/2024GL113562ng three subgroups of samples collected within narrow temperature ranges, we more effectively isolate the influence of DO. We find significant correlations between DO and the MBT′5Me temperature index in all three constant‐temperature subgroups. Underlying shifts in key brGDGT abundances indicate the problem is likely to manifest in virtually all existing calibrations. The effects …

A Microgravity Investigation Of The Subsurface At The United Arab Emirates University Campus, Fidha Farzana Ismail

Theses

This thesis investigates subsurface structures within the United Arab Emirates University (UAEU) campus using microgravity survey. Gravity methods are widely used in geophysical exploration to detect density variations that may indicate subsurface anomalies. The primary objective of this research is to generate the Bouguer anomaly map of the UAEU campus to map subsurface structures and to assess potential geological hazards such as cavities. A total of 76 gravity stations were measured across the UAEU campus using the Scintrex CG-6 gravimeter. The acquired gravity data underwent standard processing to obtain the Bouguer anomaly, including tidal, instrumental drift, latitude, free air, Bouguer, …

Monitoring Sand Migration In Al Ain City Utilizing Remote Sensing Techniques, Sanad Salem Mohammad Fareaa

Theses

Sand migration significantly impacts urban development, infrastructure, and ecosystems in arid regions such as Al Ain city, United Arab Emirates (UAE). This study employs advanced remote sensing techniques to monitor and predict sand dune migration across the Sieh Al Hama dune field, a critical area west of Al Ain. The research objectives include quantifying dune migration rates over three years (2018–2020) using monthly Sentinel-2 satellite imagery, identifying distinct dune fields, and analyzing the textural and mineralogical properties of dune sediments to infer their provenance. Field sampling from four dunes (Large Sabra Dune, Dune 1, Dune 2, and Dune 3) was …

Study Of Falāj Pathways And Their Unknown Extension In Al Ain City Using Geophysical Methods, Saud Mohammed Alsenaani

Theses

Historically, the city of Al Ain has relied on its Falāj systems as historic water resources for freshwater, which is vital for drinking and irrigating its oases and essential for supporting life in the region for centuries, providing the foundation for communities and farming. The remarkable rainfall in 2024 uncovered several hidden ancient Falāj systems and newly enlarged versions of previously recorded ones, highlighting the importance of ongoing research for their preservation. This research project aims to examine the current Falāj systems in Al Ain, particularly Falāj Mezyad, using geophysical methods to identify uncharted extensions and to examine current Falāj …

Increasing Annual Rainfall As Recorded At Five Weather Stations In The Cedar River Watershed And Adjacent, Eastern Iowa, Lee S. Potter

The Compass: Earth Science Journal of Sigma Gamma Epsilon

Monthly and annual rainfall totals were examined from five weather stations in and near the Cedar River watershed in eastern Iowa. The basin has headwaters in southern Minnesota and trends northwest to southeast across the eastern part of the state. Graphical presentation highlights noisy signals within these, with annual values showing increase of about 4 to 7 inches over the most recent 100 years. This information is presented without reference to correlation with broader climate signals to inform residents and policy makers of the increasing trend. Monthly totals show consistent increase April and June, with lesser increases in May, July, …

Sigma Gamma Epsilon – Call To Convention: Final Notice And Convention Schedule, Scott R. Beason

The Compass: Earth Science Journal of Sigma Gamma Epsilon

No abstract provided.

Material Point Method Computer Simulations Of The Tharsis Region Mars Forming From An Impact-Driven Antipodal Event: Program Development And Validation, Timothy L. Nikoley, Daniel Hunter, Michael W. Roth

The Compass: Earth Science Journal of Sigma Gamma Epsilon

The planet Mars has features that suggest uprisings could have been created by antipodal events driven by the focusing of seismic waves generated by impact. To investigate the feasibility of such a process resulting in observed features, we have developed a hybrid Newtonian dynamics-Material Point Method (MPM) computer program modeling impact to the surface of Mars, and have carried out extensive computer simulations and data analysis. In this first of two companion papers, we present the theoretical background behind the code development, remarks about program validation and typical visuals.

The Compass - Volume 94 Issue 2 - Complete Issue, Scott R. Beason

The Compass: Earth Science Journal of Sigma Gamma Epsilon

No abstract provided.

Exploring Biostimulant Efficacy Under Limited Fertilizer And Water In Utah's Watermelon Production, Evan Christensen, Milena Maria Tomaz De Oliveira, Prakriti Nepal, Youping Sun

Plants, Soils, and Climate Faculty Publications

The western U.S. has recently experienced some of the driest conditions on record, and Utah has been in a multi-year drought (2019-2023) that affected the agricultural sector, including vegetable producers. While vegetables are not a primary agricultural crop in Utah, they are still an important part of the horticultural economy with 763 farms growing 6,138 acres. As the fourth largest acreage vegetable crop in Utah (almost 10% of the acreage) watermelon and related crops in the gourd family Cucurbitaceae (nearly 36% of total vegetable acreage) are important to vegetable growers. Watermelon is a water-intensive crop and requires an adequate supply …

Dual Quaternions For Gravity Recovery Missions, Ryan Kinzie

Doctoral Dissertations and Master's Theses

A dual quaternion-based modeling, state estimation and control approach is introduced as a better alternative to the traditional methods which are currently utilized for gravity recovery missions. The proposed modeling and control approach was verified against and compared to the tangent bundle to Special Euclidean Group 3 through MATLAB simulations. The dual quaternion-based approach shows superior performance over traditional linearized and uncoupled methodologies, in both modeling accuracy of spacecraft translational position, and the ability to control the pose of a test mass relative to its host spacecraft. Utilizing data products from the Gravity Recovery and Climate Experiment Follow-On mission, a …

Integrated Geophysical Modeling Of Newly Identified Pseudofaults Within Southern Cascadia Subduction Zone, Morgan R. Madsen

Honors Program: Senior Projects (Public)

The Cascadia Subduction Zone, located off the western coast of North America, has a long history of seismic activity, causing various geohazards such as megathrust earthquakes and tsunamis for the coastal population (Goldfinger et al., 2000; Tréhu et al., 2022). It is necessary to identify areas of greater risk, as seismic hazards will continue to affect the area due to ongoing subduction of the oceanic Juan de Fuca plate beneath the North American continent. Heavily fractured, weakened zones of oceanic crust, known as propagator wakes and pseudofaults, have been shown to correlate with greater seismicity (Ashraf and Filina, 2023a). Propagator …

Coastal Erosion In Ireland, Brian Nguyen, Jeanne Sumrall

SACAD: Scholarly Activities

Ireland's approach to managing its coastlines focuses more on a short-term solution method rather than long-term, eco-friendly solutions. Their coastal defenses are created upon an immediate need without clear policies and sufficient research. As a result, beach ecosystems are frequently damaged, and the erosion is only reduced to a certain extent. To reduce erosion and protect both the environment and Irish culture, this study suggests that Ireland should implement national policies focused on regularly monitoring coastal erosion, researching nature-based solutions, and implementing them to address the problem. Moving forward, it’s important for research to focus on understanding the overall impact …

Assessing Groundwater Availability And Land Subsidence Risk Associated With Anthropogenic Activities In A Complex Aquifer System, Aya Bakr Attya Mohamed

LSU Doctoral Dissertations

The Southern Hills aquifer system (SHAS) is the primary source of water in the Capital area of Louisiana. However, the overexploitation of freshwater-bearing aquifers and the presence of two active faults, the BR fault and the DSS fault, have resulted in groundwater depletion, saltwater intrusion, and increased the risk of land surface subsidence. Such critical issues pose substantial threats to groundwater availability and exert detrimental effects on the environment and urban infrastructures. This dissertation presents a comprehensive investigation of the SHAS for recognizing the consequences of groundwater depletion and its potential long-term impacts on groundwater availability and land stability. A …

Efficiency Of Labor In Winter Pruning Of Apple Trees Using Technological Innovations, Élio Fillipi Dos Santos, Wendel Paulo Silvestre, Lessandra Silva Rodrigues, Carine Cocco

School of Earth, Environmental, & Marine Sciences Faculty Publications

The increase of new technologies in fruit-growing crops has increased productivity in cultural practices and helped farmers expand their production areas. This work aimed to quantify labor performance in winter pruning of apple trees, using manual and electronic scissors associated with utilizing a pruning platform and ladders. The treatments consisted of two types of pruning shears and two support systems. A pruner carried out pruning for 16 days, with a journey of 10 h per day. The average yield in manual pruning with a ladder was 21.35 plants pruned per hour per man. Using a platform, the yield increased to …

New Petrographic And Geochemical Constraints On Pre-Eruptive Storage Conditions And Their Control On Eruptive Styles In Martinique’S Recent Volcanic Systems, Abigail Martens

USF Tampa Graduate Theses and Dissertations

This dissertation investigates the volcanic systems of Martinique Island, focusing on magma storage conditions, magmatic evolution, and eruption dynamics. Chapter 3 presents a petrographic analysis of volcanic rocks from the island’s old, intermediate, and recent arcs, examining the evolution of plagioclase textures and the increasing abundance of other mineral phases, such as pyroxene, amphibole, olivine, and quartz, which provide insights into changing magmatic conditions. The main research is divided into two projects. Chapter 4 addresses the pre-eruptive storage conditions (pressure and temperature) of magmas beneath recent (<5 Ma) volcanic complexes (Morne Jacob, Piton du Carbet, Trois Îlets, Mt. Conil, and Mt. Pelée), exploring magma evolution, crystallization, and the role of lower crustal injections and flank collapses in triggering eruptions. Results reveal variable magma storage depths (<6 km), with significant temperature and pressure variations, indicating complex magmatic systems. Chapter 5 focuses on the Roches-Genty ignimbrite in southwestern Martinique, investigating its stratigraphy, geochemistry, and age using field mapping, grain size analysis, and 40Ar/39Ar dating. The study identifies two distinct sub-Plinian eruptive phases associated with the Dizac ignimbrite, with ages of 3.37 ± 0.14 Ma and 2.10 ± 0.26 Ma, providing insights into past explosive volcanic activity. Geochemical analysis confirms an andesitic composition, similar to regional volcanic systems. This dissertation enhances understanding of Martinique’s volcanic history, providing valuable insights into magmatic processes and eruption dynamics, with implications for volcanic hazard assessments in the Lesser Antilles.

Quaternary Subsurface Characterization Of The Mississippi River Valley Alluvial Aquifer: Insights From Interval Kriging And Airborne Em-Borehole Data Integration, Yuqi Song

LSU Doctoral Dissertations

The Pleistocene period significantly contributed to the formation of alluvial aquifer worldwide. These productive aquifers are crucial for domestic, industrial, and agricultural water supplies. The Mississippi River Valley alluvial aquifer (MRVA), a principal aquifer in the U.S., is crucial for national food security and global agricultural supply. This study aims to characterize the subsurface architecture of the MRVA, thereby enhancing fundamental understanding of sedimentological processes involved in the genesis of glacio-fluvial aquifers worldwide. The research objectives are threefold: (1) to provide a detailed characterization of the MRVA; (2) to develop 3D geostatistical methods for geological modeling; and (3) to develop …

College Of Natural Sciences 2024 Year-End Publication, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Page 2 Dean's Message
Page 3 Department Highlights
Page 4 One Day for State
Page 5 New Students in Wecota
Page 6-8 Faculty Excellence
Page 9 SDSU Physics Students Recognized
Page 9 Prairie Doc Watch Party
Page 10-11 Student Excellence
Page 11 Connections Abroad
Page 12-13 CNS’s Research Centers
Page 14 Connections Abroad
Page 14 Dean Wolf-Hall Retired
Page 15 Outreach Program
Page 15 Events and Traditions
Page 16 Student Spotlight
Page 17 Alumni Spotlight
Page 18-19 SDSU Alum at Paris Paralympics
Page 20 Work Anniversaries & Programs

Bear Lake Water Quality And Chemistry: 114 Years Of Water Management, Connely Baldwin

Spring Runoff Conference

Motivation: Fall 2024 Bear Lake Sediment-Nutrient Reduction Workshop (Bear Lake Watch) motivated deeper dive into water quality and chemistry status and trends

Development Of A Low-Cost Stem Dendrometer For Irrigation Scheduling In Fruit Trees, Anderson Luiz Dos Santos Safre, Alfonso Torres-Rua, Brent Black

Spring Runoff Conference

Motivation 

• Irrigation scheduling in water scarce regions. 
• Water stress evaluation in tart cherry orchards.
• Plant-based methods more suitable for tree crops. 
• Elevated cost of commercial dendrometers (> 1,000 USD). 

Parrotfeather (Myriophyllum Aquaticum): Biology And Management Options In Utah, Francielli S. De Oliveira

Spring Runoff Conference

Parrotfeather (Myriophyllum aquaticum)

• Invasive weed from South America.
• Heterophilic perennial dioecious plant (female in the US).
• Forms dense mats, blocks waterways, and outcompetes native species
• Spreads via rhizomes, stolons, and stem fragments.

Comparing Two Methods To Monitor Singlet Oxygen Production In Aquatic Systems: Chemical Probe Vs. Time Resolved Phosphorescence., Monika Madhiyan

Spring Runoff Conference

What’s in water?

• DOM is a naturally occurring complex mixture of organic matter
• Pollutants from domestic, industrial and agricultural effluent are introduced into surface waters

Innovative Genetic Methods For Predicting Microcystin Toxin Production In Cyanobacterial Blooms: Real-Time And Pre-Bloom Public Health Monitoring, Liyuan Hou

Spring Runoff Conference

EQL emphasizes an integrated engineering and science approach to the environmental quality of land, water, and air