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Constraining Magma Oxidation State Through Zircon Trace Elements: Estimating Tungsten Mineralization Potential In Northeastern Washington, Robin Gaudette

All Master's Theses

The oxidation state of a magma (measured by oxygen fugacity, fO₂) controls what reactions are favored during crystallization and what elements are concentrated and potentially precipitated into minerals, making it a key factor in ore-forming processes as some commodity elements are best concentrated under specific redox conditions. Tungsten (W) is best concentrated under reducing magmatic conditions, a characteristic that makes constraining magma oxidation state, done through analysis of zircon trace elements, an essential tool in plutonic tungsten deposit exploration.

This research analyzes the zircon trace elements of several Cretaceous-age intrusions in the region surrounding the now-inactive Germania tungsten …

Glacial Deposits, Vol. 48, 2024, Department Of Geography, Geology, And The Environment

Glacial Deposits

Newsletter of the Department of Geography, Geology, and the Environment

The Effect Of Seasonal Ice Cover Duration On Shoreline Erosion In Lake Michigan, Ryan S. Navarre

Dissertations, Master's Theses and Master's Reports

Shoreline erosion in Lake Michigan has been a significant concern for coastal management. Promoting coastal stability and resilience is paramount to protecting these environments, especially amid climate change. While several factors are key in understanding shoreline erosion, seasonal ice cover duration is a prominent yet understudied factor in the Great Lakes region. Here, the relationship between ice cover duration and shoreline erosion rates is assessed across 7 regions of Lake Michigan. An ice cover duration dataset was created for Lake Michigan for 2011 – 2020 and its shorelines were digitized for years with available high-resolution aerial imagery. The statistical relationship …

Coal As A Resource For Rare Earth Elements In West Virginia, Rachel Elizabeth Yesenchak

Graduate Theses, Dissertations, and Problem Reports (ETD)

Although rare earth elements and yttrium (REY) are essential for manufacturing technologies vital to economic and national security, the U.S. is heavily reliant on foreign imports of these critical metals. There is significant interest in identifying and developing unconventional REY resources including coal and coal-byproducts to help secure domestic supplies of these elements. Appalachian Basin coals and byproducts are particularly enriched in REY. Coal-producing states within the basin, including West Virginia, can utilize existing infrastructure and legacy coal mining wastes to transition into the production of REY. However, in order to develop these resources, it is critical to understand the …

(Non-) Recovery Of An Agricultural Stream From Straightening And Dredging, Aras Anderson Mann

Graduate Theses, Dissertations, and Problem Reports (ETD)

In recent history, natural, meandering streams have been straightened and dredged to reduce flooding. While this practice can be effective in reducing flooding locally, it often results in the degradation of stream water quality and aquatic ecosystems. A straighter channel inherently increases the stream gradient, which could increase flow velocity, shear stress, and potentially downstream sediment yield. Studies have shown that straightened, channelized streams often begin to return to a meandering pattern 35-50 years post-channelization. Yet cross-sectional surveys and air photo analysis of the stream reach in this study, Deckers Creek, indicate little to no observable trend of the stream …

Novel Re-Crosslinkable Preformed Particle Gels (Rppg) For Parent- And Infill-Well-Fracture Interactions Mitigation, Xiaojing Ge, Adel Alotibi, Ahmed Al-Hlaichi, Yanbo Liu, Tao Song, Junchen Liu, Baojun Bai, Thomas P. Schuman

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Hydraulic fracturing treatments in unconventional infill (or "child") wells can be significantly affected by depletion from existing parent-well, resulting in asymmetrical fracture growth. These issues may lead to excessive load-water production, proppant deposition, casing deformation in the parent well, and unbalanced stimulation of infill wells. To mitigate these effects, various strategies have been proposed, including the use of far-field diverters in child wells and repressurization of parent wells. Additionally, an increasingly popular strategy involves injecting near-wellbore diverters to temporarily plug entry points into the parent wellbores during frac operations on infill wells. To achieve better application, a novel low-cost, self-degradable, …

Comparative Analysis Of Critical Bond Strength Parameters Of Neat Class G Cement And Fly Ash Enhanced Cement To Steel, C. M. Potter, Andreas Eckert, James A. Jones, Z. Weicheng, M. Meng

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

In subsurface engineering applications, such as wellbore integrity, the interface between cement and steel is integral to expected functionality. The interface between steel and cement is often a structural weak point in many systems, however, the critical parameters for debonding evaluation are poorly understood and derived from outdated experimental procedures. Through experimental debonding tests, this study aims to analyze the tensile bond strength and fracture parameters and their sensitivity to cement composition with a pozzolanic additive (fly ash). Neat Class G cement testing resulted in an average tensile bond strength of 0.223 MPa, an average contact stiffness of 2.94x108 N/m3, …

Transport And Fate Of Nitrate In A Saturated Buffer Zone As Assessed With A Chloride Tracer Test, Alhassan Sahad, Eric W. Peterson

Faculty Publications - Geography, Geology, and the Environment

The Upper Mississippi Basin, which includes Illinois, has highly fertile soils and experiences intensive agricultural practices. Although fertile, the soils do not drain well, resulting in the installation of tile-drainage systems. The practices of tile systems coupled with the application of nitrogen-rich fertilizers have led to the excessive export of nitrate from the agricultural fields into surface waters, contributing to eutrophication and the development of hypoxic zones in aquatic environments. Saturated riparian buffer zones (SRBs) have been proposed as a means to reduce the amount of nitrate discharged from tile-drained waters into streams. Previous works show a reduction in the …

A Cytosine Analogue 5-Azacitidine Improves The Accumulation Of Licochalcone A In Licorice Glycyrrhiza Inflata., Xiaoling Ma, Ningxin Jiang, Jingxian Fu, Yuping Li, Lijun Zhou, Ling Yuan, Ying Wang, Yongqing Li

Plant and Soil Sciences Faculty Publications

Licochalcone A (LCA) is a characteristic compound of Glycyrrhiza inflata with anti-inflammatory, antioxidant and antitumor activities. However, G. inflata produces LCA in low quantities that does not meet the market demand. In this study, we found that DNA methylation inhibitor 5-azacitidine (5-azaC) successfully improved the LCA contents in G. inflata seedlings. Transcriptome analysis revealed a series of differentially expressed genes (DEGs), including transcription factors such as MYB, ERF, WRKY, and some structural genes related to flavonoid biosynthesis. However, whole genome bisulfite sequencing (BS-seq) results showed little effect of the 5-azaC treatment on the alteration of DNA methylation on these genes, …

Fluid-Rock And Fluid-Steel Interaction In Geothermal Energy Development In The Appalachain Basin, Samuel H. Bowman

Graduate Theses, Dissertations, and Problem Reports (ETD)

The ever-increasing demand for clean energy requires creative solutions. In the United States, unconventional energy sources such as geothermal are conventionally limited to the western half of the country. The Appalachian Basin in the Eastern United States is one such possible creative solution, although the comparatively low temperature gradient presents a significant challenge to delivering economically feasible geothermal energy. An emerging technology is enhanced geothermal systems, these are engineered reservoirs where a working fluid (typically water) is cycled between the subsurface energy source and the energy collection facility at the surface. The liquid water interacts with the geothermal reservoir rock …

Measuring And Modeling Riparian Wetland Saturated Hydraulic Conductivity, Nutrient Concentrations And Shallow Groundwater Dynamics In An Appalachian Mixed Land Use Catchment, Bidisha Faruque Abesh

Graduate Theses, Dissertations, and Problem Reports (ETD)

The paucity of research on accurate predictions of saturated hydraulic conductivity (Ksat), spatiotemporal analysis of nutrient concentrations relative to water source types (stream and shallow groundwater (SGW)), water flow directions, and land use in riparian wetlands of Appalachian mixed land use catchments underscored the need for this study. Additionally, the lack of SGW flow simulations and stream-SGW interactions using three-dimensional (3D) numerical models (i.e., MODFLOW) in these riparian wetlands further highlighted the research gap. Observed data including soil properties, Ksat, surface water (SW) and SGW levels, and nutrient concentrations, including nitrate (NO3-N), nitrite (NO2-N), ammonium (NH4-N), orthophosphate (PO43-P), total nitrogen …

Advances In Machine Learning Aided Seismic Interpretation And Inversion For Subsurface Characterization, Tobi Micheal Ore

Graduate Theses, Dissertations, and Problem Reports (ETD)

Geophysical data are used to “remotely sense” the subsurface to illuminate structures, stratigraphy, and features that are of interest in the exploration for energy, suitable storage for carbon dioxide, geothermal development, and environmental considerations. The interpretations of these data typically are regarded as partially an art, as it depends on the experience of the interpreter. This is further exacerbated with the big data era as this data is large and takes several days, even longer, to manually interpret. To bridge this gap of speed and subjective bias, machine learning has been successfully applied to automate the geophysical interpretation process. This …

A Gis Tool For Optimal Forage Species Selection, David B. Hannaway, Christopher Daly, Michael D. Halbleib, Linda Brewer, Sophie Baur, Chelsea Clark, Emilie Krecklow, Scott Bassett

IGC Proceedings (1977-2023)

To determine appropriate forage species for US ecoregions, geographic information technologies (GIS) are being used to create climatic and soil factor maps. Excel spreadsheets and RStudio are used to create response functions of forage species to minimum and maximum temperature, annual precipitation, soil pH, soil salinity, and salinity. National forage data and expert opinion will evaluate quantitative tolerances, seasonal yield profiles, and pollinator suitability. These maps and agronomic and livestock use information will be shared with forage specialists and farmers to provide alternatives for improved perenniality, increased diversity, and system circularity. Future work will include development and evaluation of climate …

Exploring The Consistency Of Flow Regimes Within And Among Ecoregions Of The Southeastern United States, Frank Paul Braun Iv

College of Graduate Studies: Theses & Dissertations

Human manipulation of river systems has long been a known contributor to the loss of freshwater biodiversity. By accounting for environmental causes of hydrologic variation among rivers, we can better understand how ecoregion mediates flow regimes and forecast species that may be at risk. Presumably, natural variation associated with ecoregion boundaries exerts strong influence on flow regimes, and may mediate relationships between other features (e.g., land use, dam operations) and hydrology. However, such between-ecoregion variation is poorly investigated, particularly at fine spatial and temporal scales. I characterized 10 hydrologic metrics, representing the five key dimensions of the flow regime (magnitude, …

Keynote Address And Meeting Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

Instructions To Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

Table Of Contents, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

Business Meeting Report (Secretary's And Treasurer's Report), Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

Journal Acknowledgements And Editorial Board, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

Academy Presidents And Institutional Members, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

Journal Of The Arkansas Academy Of Science Volume 78, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

A Hybrid Algorithm To Dual Sparse Sampling Measurement In Time-Resolved Electromagnetic Near-Field Scanning, Yanming Zhang, Steven Gao, Lijun Jiang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Time-resolved electromagnetic near-field scanning is vital for antenna measurement and addressing complex electromagnetic interference and compatibility issues. However, the swift acquisition of high-resolution spatiotemporal data remains challenging due to physical constraints, such as moving the probe position and allowing sufficient time for sampling. This paper introduces a novel hybrid approach that combines Kriging for sparse spatial measurement, compressed sensing (CS) for sparse temporal sampling, and dynamic mode decomposition (DMD) for a comprehensive analysis of dual-sparse sampling electromagnetic near-field data. CS optimizes sparse sampling in the time domain, capitalizing on the inherent sparsity within electromagnetic radiated signals, resulting in reliable representation …

A Data-Driven Approach To Time-Domain Electromagnetic Modeling Based On Dynamic Mode Decomposition, Yanming Zhang, Steven Gao, Lijun Jiang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

This paper presents a data-driven methodology that utilizes Dynamic Mode Decomposition (DMD) for the time-domain (TD) electromagnetic (EM) modeling of microwave devices. As an unsupervised machine learning technique, DMD leverages a limited set of unlabeled spatio-temporal electromagnetic (EM) data to determine DMD eigenvalues and eigenmodes. Then, the obtained DMD model reconstructs the dynamics as a series of exponential terms based on linear assumptions. The effectiveness of this approach is demonstrated through the TD EM modeling of photonic crystal waveguides. Comparative analysis with the finite-difference time-domain (FDTD) method shows that the DMD model not only achieves precise modeling but also facilitates …

Would Self-Supported Fracture Contribute To The Hydrocarbon Production In Shale Reservoir Besides Proppant-Supported Fracture, Y. Sun, G. Li, S. Zeng, J. Wu, J. Liu, M. Xu, C. Dai, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

During hydraulic fracturing in deep shale gas reservoirs, it is difficult to pump proppants long distances, and self-supported fractures are formed at the far and upper ends of the fractures. The self-supported fracture could hold the fracture space by its surface structure again fracture closure. However, it faces various aspects of impairment during shale gas reservoir development, which affect its conductivity. Among the impairment, long-term production results in a decline of bottom hole pressure, which will compact the fracture space, and self-supported fractures without proppant are more sensitive than those with proppant. In this paper, we conducted a series of …

An Unsupervised Learning Framework For Determining The Excitation Coefficients Using Near-Field Antenna Measurements, Yanming Zhang, Peifeng Ma, Steven Gao, Lijun Jiang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

This article presents a novel unsupervised learning framework based on multiscale dynamic mode decomposition for determining the excitation coefficients of antennas using time-domain near-field measurements. The proposed framework integrates temporal multiscale analysis to extract a joint distribution of frequency, damping factors, and spatial modes, enabling precise extraction of excitation frequencies, rising/falling edges, and phases without labeled data. We validate the effectiveness of the proposed approach through two examples involving on-off keying modulation and a phase-shift dipole antenna. It is found that the proposed method performs well in handling nonstationary excitation signals and proves particularly advantageous for calibrating tunable antenna systems. …

Tracing Past Climate Signals Through Multi-Proxy Analysis: Insights From Sedimentary Plant Wax Hydrogen Isotope Data And Long-Term Hydroclimate Records In Estonia, Mariliis Eensalu

Graduate Research Theses & Dissertations

In light of the rising global temperatures, there is an increasing need to understand the potential shifts in hydroclimate. Past climate reconstructions offer a glimpse into the possible temperature-moisture dynamics by providing quantitative constraints for hydroclimate variability under different temperature conditions, which can ultimately aid in decreasing the uncertainty in future climate projections. The research presented in this dissertation focuses on utilizing various proxies to reconstruct past hydroclimate conditions, particularly in the Baltic region, with a specific emphasis on Estonia. The second and third chapter aim to improve the understanding of sedimentary plant wax hydrogen isotope (δ2H) data by first …

Alfred Russel Wallace Notes 29. Extraterrestrial Entertainment: Are We Being Monitored By Alien Beings?, Charles H. Smith

Faculty/Staff Personal Papers

Alfred Russel Wallace (1823−1913) was an early advocate for the rational assessment of likelihood of extraterrestrial life. Current efforts to evaluate the situation have ranged from the heavily self-indulgent to the more objective, and it is still often difficult to decide just how much of the information we are receiving on the subject is dependable. An attempt is made here to cut through the haze and reduce the matter to elementals.

10be Dating Of Last Glacial Maximum Moraines And Subsequent Glacial Retreat In Chirripó National Park, Costa Rica, Caleb Emeka Okpala

Dartmouth College Master’s Theses

During the Last Glacial Maximum (LGM; ~26-19 ka) and Termination 1 (~19-12 ka), the expansion and retreat of glaciers across the Southern and Northern Hemispheres, as well as other paleoclimate proxies, document a complex pattern of global climate change. While the timing and magnitude of LGM cooling and subsequent warming is relatively well constrained in mid- and high-latitude regions across both hemispheres, less information is available about climate changes in the tropics. To provide more information about tropical climate conditions during the LGM and Termination 1, I mapped and dated the extents of past glaciers in two valleys in Chirripó …

Dust-Driven Mechanism For Marine Particle Aggregation: Interactions Between Clay Minerals, Heterotrophic Bacteria And Organic Matter Influences Aggregation In Marine Systems, Vignesh Gokuladas Menon

Dartmouth College Master’s Theses

Atmospheric dust deposition plays a crucial role in marine biogeochemical cycles, yet mechanisms underlying its impact on particle dynamics remain unclear. This study investigates the synergistic interactions between marine heterotrophic bacteria and clay minerals in seawater, focusing on their effect on Transparent Exopolymer Particles (TEP) production and organoclay aggregation. Field experiments in the Gulf of Maine and laboratory roller tank studies were conducted using natural microbial communities and model heterotrophic bacterial strains (Alteromonas sp. EZ55, Marinobacter adhaerens HP15, and Sulfitobacter sp. NAS-14.1). Results demonstrate that clay exposure significantly enhances TEP production by bloom-associated heterotrophic bacteria, with increases up to …

A General Framework For Modeling Subregional Path Effects, T. E. Buckreis, P. Wang, S. J. Brandenberg, J. P. Stewart

Civil & Environmental Engineering Faculty Publications

Next Generation Attenuation (NGA) West2 ground motion models (GMMs) include regional path adjustments for broad jurisdictional regions, which necessarily averages spatially variable path effects within those regions. We extend that framework to account for systematic variations in attenuation within subregions defined in consideration of geologic differences. In recent years, cell-based methods which systematically account for spatial variations by summing the attenuation effects over a fine discretization of uniform-rectangular cells (e.g., Dawood and Rodriquez-Marek 2013; Kuehn et al. 2019) have been shown to be an effective alternative to regionalization and a step towards modelling non-ergodic path effects. The main drawbacks of …