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Basal Topography And Carbon Accumulation Rate Of A Rare Northern California Coastal Fen, Sarah Leidinger 2024 Humboldt State University

Basal Topography And Carbon Accumulation Rate Of A Rare Northern California Coastal Fen, Sarah Leidinger

Cal Poly Humboldt theses and projects

Increasingly, the importance of peatlands as biodiversity hotpots, year-round water storage features, and significant carbon sinks are being recognized. Despite this, they are one of the most vulnerable ecosystems globally. While some peatland conservation and restoration initiatives are being developed, a greater understanding of small peatlands is needed to make management decisions. This study aims to determine the timing of peat formation, peat volume, and carbon accumulation rates of the Conspicuous Scoop Fen, a small (2.1-acre) fen near Bridgeville, California (~840 m.a.s.l.). During the summers of 2022 and 2023, I collected 39 m of peat cores at 14 sampling locations. …


150, Scott Brande 2024 University of Alabama at Birmingham

150, Scott Brande

All 3D Rock Models

Model 150 - pegmatite - igneous rock

SketchFab link: https://sketchfab.com/3d-models/150-135e099a4d4145848c7f26c0c2d5c438


190, Scott Brande 2024 University of Alabama at Birmingham

190, Scott Brande

All 3D Rock Models

Model 190 - sandstone - sedimentary rock

SketchFab link: https://sketchfab.com/3d-models/190-29d202409b1246a1b550db9c6f41b25c


220, Scott Brande 2024 University of Alabama at Birmingham

220, Scott Brande

All 3D Rock Models

Model 220 - slate - metamorphic rock

SketchFab link: https://sketchfab.com/3d-models/220-39857764278746049e60bd9238ed3891


247, Scott Brande 2024 University of Alabama at Birmingham

247, Scott Brande

All 3D Rock Models

Model 247 - schist - metamorphic rock

SketchFab link: https://sketchfab.com/3d-models/247-aea85a461ca2414489bd0b04a4df3bdcN


260, Scott Brande 2024 University of Alabama at Birmingham

260, Scott Brande

All 3D Rock Models

Model 260 - breccia - sedimentary rock

SketchFab link: https://sketchfab.com/3d-models/260-6711f31b529448739ead7cf0a33b94ee


262, Scott Brande 2024 University of Alabama at Birmingham

262, Scott Brande

All 3D Rock Models

Model 262 - breccia - sedimentary rock

SketchFab link: https://sketchfab.com/3d-models/262-5a77a879cec743c3b724644ce5490914


265, Scott Brande 2024 University of Alabama at Birmingham

265, Scott Brande

All 3D Rock Models

Model 265 - gneiss - metamorphic rock

SketchFab link: https://sketchfab.com/3d-models/265-9ea30b81d35c49d1bb066367002d1fac


271, Scott Brande 2024 University of Alabama at Birmingham

271, Scott Brande

All 3D Rock Models

Model 271 - marble - metamorphic rock

SketchFab link: https://sketchfab.com/3d-models/271-370135d0aba44ec38c87c827123db334


Beach Erosion And Recovery Since Hurricane Ivan In 2004 Along A Headland-Bay Coast In Treasure Beach, Jamaica, Elandé Engelbrecht 2024 Missouri State University

Beach Erosion And Recovery Since Hurricane Ivan In 2004 Along A Headland-Bay Coast In Treasure Beach, Jamaica, Elandé Engelbrecht

Graduate Theses/Dissertations

Anthropogenic climate change is causing sea-level rise and shoreline changes that threaten the environment and economy of coastal communities in Caribbean Island nations. To assess this risk, this study quantifies shoreline changes at Treasure Beach in St. Elizabeth Parish on the south coast of Jamaica from 2001 to 2023. The effects of storm events on erosion were also assessed. Over 10 km of shoreline are assessed with about half being sandy pocket beaches ranging from 300 to 900 m in length, separated by rocky headlands and beach rock outcrops. Sand beach erosion trends since 2001 are assessed for seven sandy …


Constraining Magma Oxidation State Through Zircon Trace Elements: Estimating Tungsten Mineralization Potential In Northeastern Washington, Robin Gaudette 2024 Central Washington University

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 …


A New Method To Invert For Interseismic Deep Slip Along Closely Spaced Faults Using Surface Velocities And Subsurface Stressing-Rate Tensors, Hanna Elston, Michele Cooke, John Loveless, Scott Marshall 2024 University of Massachusetts Amherst

A New Method To Invert For Interseismic Deep Slip Along Closely Spaced Faults Using Surface Velocities And Subsurface Stressing-Rate Tensors, Hanna Elston, Michele Cooke, John Loveless, Scott Marshall

Geosciences: Faculty Publications

Inversions of interseismic geodetic surface velocities often cannot uniquely resolve the three-dimensional slip-rate distribution along closely spaced faults. Microseismic focal mechanisms reveal stress information at depth and may provide additional constraints for inversions that estimate slip rates. Here, we present a new inverse approach that utilizes both surface velocities and subsurface stressing-rate tensors to constrain interseismic slip rates and activity of closely spaced faults. We assess the ability of the inverse approach to recover slip rate distributions from stressing-rate tensors and surface velocities generated by two forward models: (a) a single strike-slip fault model and (b) a complex southern San …


Coal As A Resource For Rare Earth Elements In West Virginia, Rachel Elizabeth Yesenchak 2024 West Virginia University

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 …


Geochemical Phase Associations Of Rare Earth Elements And Lithium In Black Shales Of The Usa: A Study In The Appalachian And Haynesville Basins, Shailee Bhattacharya 2024 West Virginia University

Geochemical Phase Associations Of Rare Earth Elements And Lithium In Black Shales Of The Usa: A Study In The Appalachian And Haynesville Basins, Shailee Bhattacharya

Graduate Theses, Dissertations, and Problem Reports (ETD)

Critical elements are an indispensable part of the clean energy transition. In the race for alternative energy technologies, lithium and rare earth elements have a proven record of being few of the most sought-after minerals. Limited availability of conventional mineral ores warrants a need to explore, understand and exploit unconventional sources of these elements. To that end, several studies have attempted to understand the rock and mineral assemblages of diverse geological systems. This doctoral thesis focuses on understanding the geochemistry of REE and Li in sedimentary environments, particularly black shale basins in the US. A suite of samples from natural …


A General Framework For Modeling Subregional Path Effects, T. E. Buckreis, P. Wang, S. J. Brandenberg, J. P. Stewart 2024 University of California, Los Angeles

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 …


Interconnectivity Of Melt During Partial Melting And Deformation Of A Peridotite, Jordan Collins 2024 The University of Akron

Interconnectivity Of Melt During Partial Melting And Deformation Of A Peridotite, Jordan Collins

Williams Honors College, Honors Research Projects

The mechanisms that allow basaltic magma to be transported to the surface are well understood, but not much is known about how the transport channels form as the basalt melt forms at the source. I performed experiments to determine these mechanisms during general shear deformation of a natural olivine aggregate (dunite) from Anita Bay, New Zealand as it partially melts using a high pressure/temperature rock deformation apparatus. Samples were analyzed using the scanning electron microscope and I observed that melt pockets started to form at the grain scale (1-2 vol% melt) prior to becoming interconnected at the sample scale (3 …


A Tensor-Based Data-Driven Approach For Multidimensional Harmonic Retrieval And Its Application For Mimo Channel Sounding., Yanming Zhang, Wenchao Xu, A. Long Jin, Min Li, Ping Yuan, Lijun Jiang, Steven Gao 2024 Missouri University of Science and Technology

A Tensor-Based Data-Driven Approach For Multidimensional Harmonic Retrieval And Its Application For Mimo Channel Sounding., Yanming Zhang, Wenchao Xu, A. Long Jin, Min Li, Ping Yuan, Lijun Jiang, Steven Gao

Electrical and Computer Engineering Faculty Research & Creative Works

In wireless channel sounding, accurately estimating multiple parameters within a multipath signal, such as azimuth, elevation, Doppler shift, and delay, necessitates addressing the challenges posed by the multidimensional harmonic retrieval (MHR) problem. To overcome these complexities, we propose a framework based on high-order dynamic mode decomposition (HODMD) that designed for robustly estimating frequencies of interest from high-dimensional sinusoidal signals, particularly in additive white Gaussian noise conditions. The HODMD approach, a hybrid algorithm amalgamating high-order singular value decomposition (HOSVD) and dynamic mode decomposition (DMD), operates by initially decomposing observed tensorial data into a core tensor and R mode matrices through HOSVD. …


Glacial Deposits, Vol. 48, 2024, Department of Geography, Geology, and the Environment 2024 Illinois State University

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

Glacial Deposits

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


Petrologic Relationship Between Lamprophyres, Carbonatites, And Heavy Rare-Earth Element Enriched Breccias At Hicks Dome, Jarek Trela, Jared T. Freiburg, Esteban Gazel, Laurence Nuelle, Anton H. Maria, David H. Malone, John M. Molinarolo 2024 Illinois State Geological Survey

Petrologic Relationship Between Lamprophyres, Carbonatites, And Heavy Rare-Earth Element Enriched Breccias At Hicks Dome, Jarek Trela, Jared T. Freiburg, Esteban Gazel, Laurence Nuelle, Anton H. Maria, David H. Malone, John M. Molinarolo

Faculty Publications - Geography, Geology, and the Environment

New petrological, geochemical, and P–T modelling results from igneous samples clarify how carbonatite-lamprophyre magmatism, fluorite and rare earth element (REE) enrichment are petrogenetically related in southern Illinois. P–T modelling reveals that igneous rocks derive from a deep mantle carbonated source, that is consistent with trace element signatures for a fluorine-rich transition zone origin. Major element systematics suggests liquid-immiscibility with lamprophyric melts as the origin for Ca-carbonatites. Heavy REE (HREE) enrichments in Hicks Dome breccias likely formed through preferential partitioning and transport of HREE by brine-melts, exsolved from a deep carbonatite body. Brine-melts redistributed HREEs throughout the …


Transport And Fate Of Nitrate In A Saturated Buffer Zone As Assessed With A Chloride Tracer Test, Alhassan Sahad, Eric W. Peterson 2024 Illinois State University

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 …


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