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Articles 1 - 30 of 275
Full-Text Articles in Earth Sciences
The Eye: A Science-Fiction Screenplay Examining Space-Time, Meteorology, And Human Connection, Ella K. Lukowiak
The Eye: A Science-Fiction Screenplay Examining Space-Time, Meteorology, And Human Connection, Ella K. Lukowiak
Senior Theses
This thesis explores the nature of time, meteorology, and human interconnection to the universe through the lens of a science-fiction screenplay. The creative project spans a three-act, detailed outline, and a screenplay draft of Act I. It is based upon extensive scientific research regarding hurricane development, the inner workings of organizations such as the National Weather Service, Einstein’s Theory of Relativity, and the space-time continuum. I will delve into the various factors that shaped my science-fiction premise, including pivotal films such as Christopher Nolan’s INTERSTELLAR (2014) and Denis Villeneuve’s ARRIVAL (2016). Both of these filmmakers integrated complex science-fiction concepts into …
Generation Of Inner Core Anisotropy By Anisotropic Thermal Conductivity Of Iron Crystals, Prajna Paramita Das, Bruce Buffett, Daniel A. Frost
Generation Of Inner Core Anisotropy By Anisotropic Thermal Conductivity Of Iron Crystals, Prajna Paramita Das, Bruce Buffett, Daniel A. Frost
Faculty Publications
Seismic anisotropy in the Earth’s inner core refers to the observation that seismic waves travel faster along the Earth’s rotation axis than in the equatorial plane, a feature inferred from decades of global seismological observations. This directional dependence of wave speeds provides important clues about the structure, composition and dynamics of the inner core. Here we explore a coupled thermo-mechanical mechanism for the generation of inner core anisotropy, focusing on the effects of anisotropic thermal conductivity in iron crystals as the inner core cools. We propose that the higher thermal conductivity of iron along the crystallographic c-axis compared with …
Vegetation Enhances Nitrogen Removal In Stormwater Ponds In Coastal South Carolina, Darcy Perin, Annie Bourbonnais
Vegetation Enhances Nitrogen Removal In Stormwater Ponds In Coastal South Carolina, Darcy Perin, Annie Bourbonnais
Faculty Publications
Coastal development and the increase in impervious surfaces lead to greater stormwater volumes, a key contributor to nonpoint source pollution. Stormwater ponds are generally highly efficient in eliminating particle-bound nutrients, such as phosphorus, but are often much less effective at removing dissolved nutrients, like nitrogen. Excess inorganic nitrogen can lead to coastal eutrophication, harmful cyanobacterial blooms, and coastal hypoxia. However, inorganic nitrogen can be removed from the environment through several different microbially facilitated processes. This research aims to estimate the rates of nitrogen removal (i.e., by denitrification), the net N2 fluxes, and internal recycling (DNRA) across the sediment-water interface …
The Age And Composition Of The Voyager Seamounts: Evidence For A Long-Lived Marquesas Mantle Source, Andrea Balbas, Hannah Paradis, Kevin Konrad, Valerie A. Finlayson, Michael Bizimis, Stephanie Anderson, Christopher Kelley, Nicole A. Raineault, Beth N. Orcutt
The Age And Composition Of The Voyager Seamounts: Evidence For A Long-Lived Marquesas Mantle Source, Andrea Balbas, Hannah Paradis, Kevin Konrad, Valerie A. Finlayson, Michael Bizimis, Stephanie Anderson, Christopher Kelley, Nicole A. Raineault, Beth N. Orcutt
Faculty Publications
We present new observations on the dynamics and locations of deep mantle reservoirs derived from the ages and compositions of Voyager Seamount Chain lava flows. The previously unexplored Voyager Seamount Chain trends NW–SE between the Mid-Pacific Mountains and the Northwestern Hawaiian Ridge. Volcanic samples were recovered from the chain during the Ocean Exploration Trust expedition NA134. The lava flows are alkalic to highly alkalic in composition. Ages ranged from 81 to 86 Ma (n = 8), with the oldest ages in the NW and an age-progression toward the SE. The Voyager age-progression continues southward through the Northern Line Islands …
Tectonic Implications Of Transitional Melting Regimes From Petrological, Geochronological, And Compositional Characterization Of The Ophiolitic Seventymile Terrane, Alaska, Usa, Erin Todd, Johnathan Saul Caine, Michael Bizimis, Andrew R.C. Kylander-Clark, Robert Reece Hammond, Alicja Wypych
Tectonic Implications Of Transitional Melting Regimes From Petrological, Geochronological, And Compositional Characterization Of The Ophiolitic Seventymile Terrane, Alaska, Usa, Erin Todd, Johnathan Saul Caine, Michael Bizimis, Andrew R.C. Kylander-Clark, Robert Reece Hammond, Alicja Wypych
Faculty Publications
New geochemical, U-Pb geochronology, and Sr-Nd-Hf isotope data provide evidence for the tectonic evolution of the Seventymile terrane in interior Alaska, USA. Ultramafic and mafic rocks of the Seventymile terrane are thought to represent components of a dismembered ophiolite and provide unique constraints on regional terrane evolution and accretion. The Seventymile ophiolite represents fragments of the Devonian to Permian Slide Mountain Ocean (SMO) that separated allochthonous and parautochthonous continental fragments of western North America. It now occurs as multiple thrust sheets containing Permian mafic and ultramafic rocks overlying and/or possibly imbricated with amphibolite-facies supracrustal rocks of allochthonous Yukon-Tanana terrane and …
Flow Structure And Mixing Near A Small River Plume Front: Winyah Bay, Sc, Usa, Christopher Papageorgiou, George Voulgaris, Alexander E. Yankovsky, Diane Bennett Fribance
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 …
First Detrital Zircon Provenance Data From Oligocene-Pleistocene Sediment In The Beaufort-Mackenzie Basin, Arctic Ocean, Joseph Martina
First Detrital Zircon Provenance Data From Oligocene-Pleistocene Sediment In The Beaufort-Mackenzie Basin, Arctic Ocean, Joseph Martina
Theses and Dissertations
Sediment, runoff, and nutrient input to the Arctic Ocean plays a critical role in both physical and biological processes that impact regional and global systems. The Beaufort-Mackenzie Basin, situated in the Arctic Ocean offshore northwestern Canada, contains more than 14 km of clastic strata and provides a record of erosion and sediment transport from the Cretaceous to present. Pliocene sedimentation rates within the basin jump nearly 2000% relative to underlying units, but the cause of this shift remains unknown. We used cuttings from the N. Issungnak L-86 well, focusing on the Oligocene-lower Miocene Kugmallit and Mackenzie Bay sequences and the …
Mo Isotopes In The Aleutian And Costa Rican Arcs: Source Variability And Juvenile Crust Formation, Ekaterina Rojas Kolomiets
Mo Isotopes In The Aleutian And Costa Rican Arcs: Source Variability And Juvenile Crust Formation, Ekaterina Rojas Kolomiets
Theses and Dissertations
Chemical and physical transfer between the surface, lithosphere and asthenosphere at subduction zones leads to arc magmatism and continental crust (CC) production. Subduction zones magmas and associated volcanic products sample a variety of magmatic sources that contribute to their chemical compositions in various proportions. This dissertation contributes to the study of subduction zones magmatism by assessing the relative role of subduction inputs (sediments, altered oceanic crust – AOC – and serpentinite) as flux agents in the arc magmatism and in CC formation in subduction zones under the scope of Mo isotope systematics.
I present the first Mo isotope analyses form …
Integrated Coastal Science And Dune Management: A South Carolina Perspective, Michelle Harris
Integrated Coastal Science And Dune Management: A South Carolina Perspective, Michelle Harris
Theses and Dissertations
Historically, coastal dunes have been poorly understood from a societal perspective despite their protective role in attenuating incoming waves to reduce onshore flood risk. As developed coastlines promote strategies to design and maintain managed dune systems, it is necessary to ensure these strategies are optimized for dune health and resilience, particularly given the increasing threat of natural and anthropogenic stressors. This dissertation work aims to identify strategies that influence coastal dune management in South Carolina (SC), USA from an integrated approach, including a current use assessment, a mesoscale field-based study on strategy efficacy, and by incorporating a societal assessment and …
Extracting Metamorphic Histories Utilizing U-Pb Laser Ablation Zircon Geochronology From The Southern Appalachians Crystalline Rocks And Detrital Sediment, Meredith Kay Love Gawai
Extracting Metamorphic Histories Utilizing U-Pb Laser Ablation Zircon Geochronology From The Southern Appalachians Crystalline Rocks And Detrital Sediment, Meredith Kay Love Gawai
Theses and Dissertations
The southern Appalachian mountain belt is an accretionary orogen that formed in the southeastern United States through several phases of oceanic subduction and continental collision during the Paleozoic Era and culminated in the formation of the supercontinent Pangaea. Although many U-Pb zircon ages have been collected from the igneous, metaigneous and metasedimentary rocks in the crystalline core of the southern Appalachians, there remain opportunities to better reconstruct the metamorphic and magmatic history of the southern Appalachians through the lens of zircon geochronology. Such data are valuable in identifying genetic relationships between candidate terranes of the orogen. Herein, I present laser-ablation …
The Serendipity Of Discovery: Life Of A Geochemist, Willard S. Moore
The Serendipity Of Discovery: Life Of A Geochemist, Willard S. Moore
Faculty Publications
My strategy for writing this autobiography is to use examples of how working on seemingly different projects can often lead to outcomes more important than originally envisioned. Serendipity is a "happy accident"; specifically, the accident of discovering something useful without directly looking for it. This often occurs when two research projects converge unexpectedly. The main text contains examples of how serendipity has led me to important discoveries including: (a) finding surprisingly high 228Ra activities in the ocean, (b) developing a means of rapidly and quantitatively extracting radium from seawater, (c) devising a rapid, sensitive method of measuring 224Ra …
Engaging Students In The Scientific Process: An Examination Of Active Learning Strategies In Introductory Geoscience Labs, Meryssa Piper
Engaging Students In The Scientific Process: An Examination Of Active Learning Strategies In Introductory Geoscience Labs, Meryssa Piper
Theses and Dissertations
High-quality instruction of introductory geoscience courses entices students to major in geoscience fields and ensures undergraduate students have opportunities to learn and apply scientific information and practices. Prior studies indicate that active learning strategies in higher education settings can increase student knowledge and interest. This dissertation explores the integration of two active learning strategies in introductory geoscience laboratory courses: inquiry and gamification The first study housed in Chapter 2 investigates the level of inquiry used in introductory geoscience lab activities across the United States. Through a comprehensive analysis of these activities, this chapter assesses: (1) the degree to which instructor …
The Fifth Element In Three Dimensions: Boron Systematics Along And Across The Aleutian Volcanic Arc, Owen Jensen
The Fifth Element In Three Dimensions: Boron Systematics Along And Across The Aleutian Volcanic Arc, Owen Jensen
Theses and Dissertations
This study uses abundances and isotope ratios of the fluid-mobile element boron (B) to better understand the role of fluids in volcanism at the Aleutian arc in Alaska. In volcanic rocks from the Aleutian volcanic front, patterns in B abundance and isotope ratios (δ11B) point to three endmembers: a sediment melt, a slab interior melt, and a slab-top melt. Most lavas from the eastern Aleutian Islands have δ11B of -2 to +5‰, similar to Aleutian sediment. Hence, sediment is likely to be the dominant B source in the Aleutian Island samples. In lavas from the western Aleutian seafloor, high δ11B …
Size Fractionation Informs Microbial Community Composition And Interactions In The Eastern Tropical North Pacific Ocean, Madeleine A. Thompson, David L. Valentine, Xuefeng Peng
Size Fractionation Informs Microbial Community Composition And Interactions In The Eastern Tropical North Pacific Ocean, Madeleine A. Thompson, David L. Valentine, Xuefeng Peng
Faculty Publications
Marine microorganisms are drivers of biogeochemical cycles in the world’s oceans, including oxygen minimum zones (OMZs). Using a metabarcoding survey of the 16S rRNA gene, we investigated prokaryotic communities, as well as their potential interactions with fungi, at the coastal, offshore, and peripheral OMZ of the eastern tropical North Pacific. Water samples were collected along a vertical oxygen gradient, and large volumes were filtered through three size fractions, 0.22, 2, and 22 µm. The changes in community composition along the oxygen gradient were driven by Planctomycetota, Bacteroidota, Verrucomicrobiota, and Gammaproteobacteria; most are known degraders of marine polysaccharides and usually associated …
Deconvolving Provenance Signatures Of Pliocene-Pleistocene Coastal Loess Deposits Along The Atlantic Margin Of Argentina, Will Robert Quanrud
Deconvolving Provenance Signatures Of Pliocene-Pleistocene Coastal Loess Deposits Along The Atlantic Margin Of Argentina, Will Robert Quanrud
Theses and Dissertations
Dust derived from southern South America provides critical nutrients for autotropic marine biota in the South Atlantic Ocean, such that fluxes of wind-blown sediment may ultimately affect the concentration of atmospheric CO2. Expansive sand, silt, and loess deposits are exposed in Central Argentina, recording millions of years of eolian processes; however, the provenance and transport pathways of this dust remains unclear. Coastal loess deposits ranging in age from Pliocene to upper Pleistocene are present along the Atlantic margin of Argentina and provide information on sediment transport pathways for the last 4 million years. Nine samples of loess were collected and …
Investigating Arctic Ocean Freshwater Content And Circulation In A Changing Climate, Emma Louise Hoffman
Investigating Arctic Ocean Freshwater Content And Circulation In A Changing Climate, Emma Louise Hoffman
Theses and Dissertations
The Arctic Ocean is unique among the world’s oceans, characterized by its cold temperatures, salinity-driven vertical structure, and shallow shelf seas. It has warmed intensely since the 1980s at rates exceeding the global average. This Arctic Amplification drives variability in sea ice and salinity, affecting local circulation and exchange with other basins, leading to global changes in oceanic and atmospheric circulation and the biosphere. This thesis explores changing dynamics in the Arctic Ocean, in particular connecting modeled changes in liquid freshwater content (FWC) and its pathways with major ocean circulation patterns, atmospheric drivers, and large-scale climatic changes.
This research combines …
New Techniques For Studying Ocean Eddy Dynamics In The Arabian Sea And The Gulf Of Mexico, Paul Andrew Ernst
New Techniques For Studying Ocean Eddy Dynamics In The Arabian Sea And The Gulf Of Mexico, Paul Andrew Ernst
Theses and Dissertations
Coherent vortices known as eddies are ubiquitous throughout the world’s oceans and are responsible for modulating regional climates via the transfer of heat, momentum, and salt. Two regions where eddies are particularly prominent are the Arabian Sea (AS) and the Gulf of Mexico (GoM). This dissertation advances the study of eddies in these regions by developing and employing new techniques in conjunction with remotely sensed data and high-resolution ocean models. These models focus particularly on lesser-studied eddy components at the subsurface and the submesoscale (below 25 km in radius).
The first component of this dissertation focuses on the Lakshadweep High …
Assessing Multi-Annual Phytoplankton Community Compositions And Biomass Across Tidal Creek And Open Water Estuarine Habitats In South Carolina, Shannon Elizabeth Powers
Assessing Multi-Annual Phytoplankton Community Compositions And Biomass Across Tidal Creek And Open Water Estuarine Habitats In South Carolina, Shannon Elizabeth Powers
Theses and Dissertations
The urbanization of coastal environments in recent decades has caused an accelerating increase in nutrient-rich runoff from the landscape. The presence of these excess nutrients in the aquatic environment can result in degradation of water quality and harmful algal blooms. In South Carolina (SC), coastal development continues to threaten the resiliency of salt marsh estuaries, especially in combination with other stressors like climate change and sea level rise. Estuaries are important nurseries and habitats for fisheries and ecotourism. The South Carolina Estuarine and Coastal Assessment Program (SCECAP) is an ongoing monitoring program that assesses the habitat condition along the coast …
The Expression Of Mantle Seismic Anisotropy In The Global Seismic Wavefield, Jonathan Wolf, Maureen D. Long, Daniel A. Frost, Tarje Nissen-Meyer
The Expression Of Mantle Seismic Anisotropy In The Global Seismic Wavefield, Jonathan Wolf, Maureen D. Long, Daniel A. Frost, Tarje Nissen-Meyer
Faculty Publications
The dependence of seismic wave speeds on propagation or polarization direction, called seismic anisotropy, is a relatively direct indicator of mantle deformation and flow. Mantle seismic anisotropy is often inferred from measurements of shear-wave splitting. A number of standard techniques to measure shear-wave splitting have been applied globally; for example, *KS splitting is often used to measure upper mantle anisotropy. In order to obtain robust constraints on anisotropic geometry, it is necessary to sample seismic anisotropy from different directions, ideally using different seismic phases with different incidence angles. However, many standard analysis techniques can only be applied for certain epicentral …
Offshore Detachment Of The Winyah Bay Plume Through Ekman Dynamics Under Upwelling Conditions, Isabella Moore
Offshore Detachment Of The Winyah Bay Plume Through Ekman Dynamics Under Upwelling Conditions, Isabella Moore
Theses and Dissertations
ABSTRACT River plumes play a crucial role in coastal ecosystems by influencing land-ocean interactions, primary production, water quality, and ocean circulation. This study presents observations of a buoyant river plume off Winyah Bay, South Carolina (USA), conducted in 2020 and 2021. Observations comprised CTD casts and shipborne ADCP profiles as well as near surface flow measurements from a floating platform and microstructure profiles in uprising mode. This research focuses on the offshore transport of the buoyant water through Ekman dynamics under upwelling-favorable conditions. Under varying wind forcing and stratification scenarios, the Winyah Bay plume either remains near the coast or …
Calibration And Use Of The Transparency Tube As An Estimate Of Turbidity: An Analysis Of Factors Controlling Light Attenuation In Estuarine Waters, Makenna Leigh Thompson
Calibration And Use Of The Transparency Tube As An Estimate Of Turbidity: An Analysis Of Factors Controlling Light Attenuation In Estuarine Waters, Makenna Leigh Thompson
Theses and Dissertations
The transparency tube is low-cost, portable, and easy to use to measure the transparency or clarity of the water. Filling the tube with water creates a small-scale water column where water will be slowly drained out of the bottom until the Secchi disk at the bottom of the tube is visible from the top opening, and the depth of the remaining water in the tube is recorded in centimeters. Unlike traditional Secchi disk measurements, the advantage of this instrument is that sampling depth in highly turbid waters is possible with a centimeter scale resolution. Transparency tube measurement, through careful calibrations, …
The Fate Of Fixed Nitrogen In Santa Barbara Basin Sediments During Seasonal Anoxia, Xuefeng Peng, David J. Yousavich, Annie Bourbonnais, Frank Wenzhöfer, Felix Janssen, Tina Treude, David L. Valentine
The Fate Of Fixed Nitrogen In Santa Barbara Basin Sediments During Seasonal Anoxia, Xuefeng Peng, David J. Yousavich, Annie Bourbonnais, Frank Wenzhöfer, Felix Janssen, Tina Treude, David L. Valentine
Faculty Publications
Despite long-standing interest in the biogeochemistry of the Santa Barbara Basin (SBB), there are no direct rate measurements of different nitrogen transformation processes. We investigated benthic nitrogen cycling using in situ incubations with 15NO 3̅ addition and quantified the rates of total nitrate (NO 3̅) uptake, denitrification, anaerobic ammonia oxidation (anammox), N2O production, and dissimilatory nitrate reduction to ammonia (DNRA). Denitrification was the dominant NO 3̅ reduction process, while anammox contributed 0 %–27 % to total NO 3̅ reduction. DNRA accounted for less than half of NO 3̅ reduction except at the …
Enriched Regions Of 228Ra Along The U.S. Geotraces Pacific Meridional Transect (Gp15), Willard S. Moore, Matt Charette, Paul Henderson, Doug Hammond, Nathaniel Kemnitz, Emilie Leroy, Eun Young Kwon, Mikael Hult
Enriched Regions Of 228Ra Along The U.S. Geotraces Pacific Meridional Transect (Gp15), Willard S. Moore, Matt Charette, Paul Henderson, Doug Hammond, Nathaniel Kemnitz, Emilie Leroy, Eun Young Kwon, Mikael Hult
Faculty Publications
The half‐life of 228Ra (5.7 years) aligns well with near‐surface and near‐bottom ocean mixing timescales. Because 228Ra is sourced from sediments, regions of enhanced activity represent water that has recently interacted with sediments on the continental margin or seabed. The GP15 meridional transect from Alaska to Tahiti along152°W encountered several regions in the upper ocean where 228Ra was enriched. These enrichments follow surface and subsurface ocean current patterns and pair with earlier measurements of 228Ra and transient radionuclides to reveal the origins of these enriched regions. An enriched region at Alaska margin stations 1–3 was sourced locally but did not …
Petrography Study Of The Recent Sediments In Hareer’S Region At Basrah Governorate - Southern Iraq, K J. Al-Sudani, B N. Albadran, A S Y Al-Hadadi, M H. Al-Jaberi, Jennifer R. Pournelle
Petrography Study Of The Recent Sediments In Hareer’S Region At Basrah Governorate - Southern Iraq, K J. Al-Sudani, B N. Albadran, A S Y Al-Hadadi, M H. Al-Jaberi, Jennifer R. Pournelle
Faculty Publications
Two sites of Hareer’s region is located in the southern part of Iraq, specifically in the northern Basrah Governorate. The sites are at a depth of 5 meters. The results of heavy mineral analysis showed that there are fifteen types include; Opaque grain (Iron Oxide), Chlorite, Muscovite mica, Biotite, Orthopyroxene, Clinopyroxene, Amphibole (Hornblende and Actinolite), Epidote, Garnet, Kyanite, Staurolite, Zircon, and Tourmaline. On the other hand the light minerals and the results of the mineral analyses revealed that they were primarily composed of rock fragments, with a variety of quartz minerals, feldspar minerals, evaporate minerals, clay-coated grains, and trace amounts …
Understanding The Role Of The Jet Streams And Gulf Stream Eddies On The Northwest Atlantic Marine Heatwaves, Lydia Rose Duncan Sims
Understanding The Role Of The Jet Streams And Gulf Stream Eddies On The Northwest Atlantic Marine Heatwaves, Lydia Rose Duncan Sims
Theses and Dissertations
The Northwest (NW) Atlantic is one of the fastest warming regions in the global ocean and in the recent decade has experienced several extreme temperature events. These extreme anomalous temperature events are known as Marine Heatwaves (MHWs), which are forced by a variety of physical processes that affect the heat source and sink of the water column. These MHWs have been increasing globally in duration and frequency due to anthropogenic warming, and have increased ecological damage seen in mass mortality events of economically viable species. Within the NW Atlantic, several key processes encourage the formation of MHWs, such as the …
Nitrous Oxide Cycling In The Eastern Tropical North Pacific Oxygen Deficient Zone From Concentrations, Stable Isotopes And Isotopomers, Margaret Ann Gaspar
Nitrous Oxide Cycling In The Eastern Tropical North Pacific Oxygen Deficient Zone From Concentrations, Stable Isotopes And Isotopomers, Margaret Ann Gaspar
Theses and Dissertations
Nitrous oxide (N2O) is a potent greenhouse gas and ozone depleting substance. It is estimated that the ocean accounts for about one third of total atmospheric emissions, which mostly occur in Oxygen Deficient Zones (ODZs) connected to coastal upwelling regions. Modeling efforts and high-resolution datasets are starting to provide a clearer picture of global marine N2O fluxes, spatiotemporal variability, and the impacts of submesoscale processes on N2O distributions. We measured nitrous oxide concentrations, stable isotope ratios and isotopomers at 7 open ocean stations along a transect crossing the Eastern Tropical North Pacific ODZ as …
Groundwater Flow And Salt Marsh Migration: The Forest/Marsh Boundary, Camille Rossiello
Groundwater Flow And Salt Marsh Migration: The Forest/Marsh Boundary, Camille Rossiello
Theses and Dissertations
Salt marshes migrate landward in response to sea level rise, but the rate of this migration is not constant and can be influenced by pulse disturbances. Long term observations at Sapelo Island, Georgia, show that salt marsh migration has occurred during droughts, but the mechanism for this migration is unclear. Drought is thought to influence salt marsh migration by reducing fresh groundwater discharge from the upland. Rising sea level also encroaches on the upland, which could cause movement of the freshwater lens inland. A two-dimensional numerical model was built to simulate groundwater flow and solute transport based on the Marsh …
Hf Radar: Shining A Light On Ocean Currents, Douglas Cahl
Hf Radar: Shining A Light On Ocean Currents, Douglas Cahl
Theses and Dissertations
High Frequency (HF) radar systems are commonly used to estimate surface ocean currents over the coastal ocean. Their range depends on their operational frequency and low frequency systems (≤ 10 MHz) can reach distances up to 200 km from the coastline. These systems are used to estimate surface currents by measuring the phase speed of wind-driven waves and comparing the measured speed with that expected theoretically; deviations from the theoretical still-water phase speed are attributed to ocean surface currents. Although HF radar systems are considered a mature technology and the accuracy of the radar-derived surface current estimates is well studied, …
Marine Anoxia Initiates Giant Sulfur-Bacteria Mat Proliferation And Associated Changes In Benthic Nitrogen, Sulfur, And Iron Cycling In The Santa Barbara Basin, California Borderland, David J. Yousavich, De'marcus Robinson, Xuefeng Peng, Sebastian J.E. Krause, Frank Wenzhoefer, Felix Janßen, Na Liu, Jonathan Tarn, Frank Kinnaman, David L. Valentine, Tina Treude
Marine Anoxia Initiates Giant Sulfur-Bacteria Mat Proliferation And Associated Changes In Benthic Nitrogen, Sulfur, And Iron Cycling In The Santa Barbara Basin, California Borderland, David J. Yousavich, De'marcus Robinson, Xuefeng Peng, Sebastian J.E. Krause, Frank Wenzhoefer, Felix Janßen, Na Liu, Jonathan Tarn, Frank Kinnaman, David L. Valentine, Tina Treude
Faculty Publications
The Santa Barbara Basin naturally experiences transient deoxygenation due to its unique geological setting in the southern California Borderland and seasonal changes in ocean currents. Long-term measurements of the basin showed that anoxic events and subsequent nitrate exhaustion in the bottom waters have been occurring more frequently and lasting longer over the past decade. One characteristic of the Santa Barbara Basin is the seasonal development of extensive mats of benthic nitrate-reducing sulfur-oxidizing bacteria, which are found at the sediment–water interface when the basin's bottom waters reach anoxia but still provide some nitrate. To assess the mat's impact on the benthic …
Exploring The Current Training Of Undergraduate Geology Students And Teaching Spatial Skills To Improve Student Outcomes, Ann Marie Klyce
Exploring The Current Training Of Undergraduate Geology Students And Teaching Spatial Skills To Improve Student Outcomes, Ann Marie Klyce
Theses and Dissertations
Spatial skills, which represent the ability to mentally manipulate objects (Schneider & McGrew, 2012; Atit et al., 2020) have been shown to be correlated with entrance, persistence and success in STEM (Shea et al., 2001; Wai et al., 2009). Specifically, these skills have been shown to be necessary to geologists and geoscientists (Hegarty, 2014; Gagnier et al., 2016). While we recognize the importance of these skills, explicit training in them is rarely offered (NRC 2006). Consequently, cognitive scientists and discipline based education researchers have begun concerted efforts to offer training in spatial skills to improve student outcomes (e.g. Uttal et …