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Schreibersite: Synthesis, Characterization And Corrosion And Possible Implications For Origin Of Life, Nikita Latesha La Cruz

USF Tampa Graduate Theses and Dissertations

We present study of the synthesis and reactions of an analog of the meteoritic mineral schreibersite with formula (Fe,Ni)3P, believed to be a prebiotic source of reactive phosphorus that may have prompted the formation of phosphorylated biomolecules near the time of the origin of life (Pasek and Lauretta, 2005). The mineral was synthesized by mixing stoichiometric proportions of elemental iron, nickel and phosphorus and heating in a tube furnace at 820°C for approximately 235 hours under argon or under vacuum, a modification of the method of Skála and Drábek (2002). The mineral was characterized using X-ray diffractometry (XRD), X-ray photoelectron …

Atmospheric Effects On Radar/Ladar Detection Of Seismic Activity, Michelle Frances Via

Browse all Theses and Dissertations

This thesis investigates how well ground vibrations can be detected at ladar or radar wavelengths and how the atmosphere may impact the observation of such activity. First understanding atmospheric hindrances at each of these wavelengths is helpful to prioritize by those yielding best transmission results. A prerequisite to the outdoor field experiment performed for this study involves analyzing atmospheric effects characterization at six probable wavelengths using the Laser Environmental Effects Definition and Reference tool (LEEDR) developed by the Air Force Institute of Technology's (AFIT) Center for Directed Energy (CDE). These wavelengths, selected from the shortwave infrared and microwave portions of …

Stability Of Monomethylmercury In Water, Sarah Elyse Harvey

Browse all Theses and Dissertations

Monomethylmercury (MMHg) bioaccumulates in aquatic food webs, leading to concentrations in fish that increase health risks for humans who consume fish. As a result of processes that produce and decompose it, MMHg concentrations are notoriously unstable in many natural waters. I examined the stability of MMHg in both filter-sterilized (< 0.1 µm) reagent-grade water and 0.22-µm filtered sediment pore water from Grand Lake St. Marys, Auglaize and Mercer Counties, Ohio, each at three MMHg treatment concentrations (1, 5, and 50 ng/L). Reagent-grade water samples were incubated under both light and dark conditions at either 5 or 26 °C for 112 days. Pore water samples were incubated in the dark at 26 °C, mimicking environmental conditions, for a period of 98 days. Decay constants (± 95% CI) for solutions containing either 1 or 5 ng/L MMHg in reagent-grade water ranged from 0.0009 ± 0.0013 to 0.1225 ± 0.0150 d-1, with greater decay constants at higher temperature and no significant effect of light exposure. In contrast, decay constants for 50 ng/L MMHg in reagent-grade water were much less than those in more dilute solutions, ranging from 0.0018 ± 0.0015 to 0.0055 ± 0.0023 d-1, with both light and temperature influencing MMHg decomposition. Decay constants of MMHg in pore water were found to be independent of initial concentration of MMHg; however, decay constants in pore water samples were 3-fold higher than those in reagent-grade water amended with the same initial concentration (p = 0.007). These results suggest that natural constituents in pore water accelerate MMHg decay reactions.

Problems And Prospects Of Grassland Development: Policy Issues, S. Ray Smith

IGC Proceedings (1977-2023)

There are a range of government and non-government policies that affect grassland development around the world. The objective of this paper is to provide examples of successful policies which have been instrumental in the preservation and maintenance of grasslands and to highlight policies which have resulted in negative consequences. This paper will not attempt to provide a complete overview of policies, but instead will provide examples from representative countries. Policies which affect grasslands can be classified into two broad categories: government policies that cover comprehensive landscape issues like the Grassland Household Contract System (GHCS) in China or the Federal Land …

Intra- And Inter-Seasonal Variability Of Supra-Glacial 1 Streams And Lakes Over The West Greenland Ice Sheet 2 From High-Resolution Satellite Optical Data, Michael Gregory Brown

Dissertations and Theses

The Greenland ice sheet (GrIS) is one of the largest glacial ice masses on Earth, second only to the Antarctic ice sheet. The surface hydrology of the GrIS plays a crucial role on the surface energy and mass balance budgets of the ice sheet as a whole. Surface water, known as supra-glacial water, is seasonally found in the ablation zone and feeds the en-glacial and sub-glacial hydrological environments of the ice sheet. The spatial distribution of surface streams is poorly understood and their temporal variability is (to our knowledge) unknown. One of the reasons for the lack of knowledge on …

Development Of 3-D Shear Wave Models Using A Multi-Objective Optimization Scheme, Lennox Emmanuel Thompson

Open Access Theses & Dissertations

Evidence of geologic activity still occurring in Rio Grande Rift (RGR) includes quaternary faulting, seismicity, and widening at a small rate. We map the crustal thickness and seismic velocity ratio to create crustal model cross sections that highlights the regional extension of the Southern Rio Grande Rift (SRGR). Specifically, we compute receiver functions and receiver function stacks for 147 USArray and previously collected data, and interpolate the crustal and velocity results using a kriging interpolation scheme. By incorporating gravity, magnetics, receiver functions, velocity models, and the interpretation of seismic reflection/refraction data, we produce a constrained crustal model that characterizes the …

Analytical Pyrolysis Principles And Applications To Environmental Science, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Over the past half century, analytical pyrolysis has proven itself to be an effective means for the semiquantitative characterization of complex macromolecular organic substances. It has been demonstrated that instruments such as Py-FID, Py-MS, and in particular, Py-GC/MS can provide valuable geochemical insights when applied to a wide variety of problems in environmental science. The more widespread use of analytical pyrolysis methods in the evaluation of environmental pollution is recommended, because of their relatively low cost and information-rich results.

Pyrolysis is the heating of organic substances in an inert, oxygen-free atmosphere, thereby avoiding combustion. When performed on a large scale, …

Integrated Assessment Of Interactions Between Surface Water And Groundwater Under Climate Variability And Change In The White Volta Basin, Ghana, Felix Mensah Oteng

Theses, Dissertations and Culminating Projects

The Nasia River, a tributary of the White Volta River system in Northern Ghana, is an important water resource for the area. In this research, a hydrological model that is able to simulate surface and subsurface flows in the Nasia catchment reasonably well was developed. The model was calibrated and verified using discharge and hydraulic head observations for the period 2000-2010. The complete simulation showed that the model was able to simulate the streamflow at the Nasia outlet quite well (Nash-Sutcliffe coefficient of 0.65, and correlation coefficient 0.805). The flow dynamics at three groundwater monitoring stations (HAP5, HAP 10, and …

Gravity And Magnetic Investigations Into Possible Economic Mineral Deposits Within The Northwest St. Francois Terrane, Southeastern Missouri, Brandon Todd Ives

Graduate Theses/Dissertations

The exposed Precambrian St. Francois Mountains in southeast Missouri are a well-studied terrane of rhyolites, granites, and basaltic dikes, but much of the buried basement lithology west of the exposed region is still poorly delineated. The western St. Francois is host to large hydrothermal Pb-Zn and Fe-oxide ore deposits, some of which were located with previous geophysical investigations. The economic ore deposits specifically in the Pea Ridge Mine in Washington County contain known economic minerals and rare earth element deposits. In order to further investigate the Precambrian basement lithologies and the possible locations of additional economic ore deposits, a gravity …

Contribution Of Multidomain Titanomagnetite To The Intensity And Stability Of Mars Crustal Magnetic Anomalies, Stefanie A. Brachfeld, David Cuomo, Lisa Tatsumi-Petrochilos, Julie A. Bowles, Deepa Shah, Julia Hammer

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Two basalts with compositions relevant to the crusts of Mars and Earth were synthesized at igneous temperatures and held at 650°C for 21 to 257 days under quartz‐fayalite‐magnetite fO2 buffer conditions. The run products are germane to slowly cooled igneous intrusions, which might be a significant volumetric fraction of the Martian crust and carriers of magnetic anomalies in the Southern Highlands. Both basalts acquired intense thermoremanent magnetizations and intense but easily demagnetized anhysteretic remanent magnetizations carried by homogeneous multidomain titanomagnetite. Hypothetical intrusions on Mars composed of these materials would be capable of acquiring intense remanences sufficient to generate the …

Short-Term Effects Of Poultry Litter Or Woodchip Biochar Amendment In A Temperate Zone Agronomic System, Katy Elizabeth Brantley

Graduate Theses and Dissertations

Biochar, a charcoal product produced by the anaerobic thermal decomposition of biomass, can provide agronomic benefits when soil applied. However, research is lacking in temperate region soils investigating specific biochar products and their effects on agronomically important crops. A greenhouse study utilizing poultry litter biochar and a field study utilizing pine woodchip biochar were conducted to observe the effects of biochar application to Northwest Arkansas soils on corn growth and nutrient availability. A third experiment investigated poultry litter and pine woodchip biochar influences on soil water retention. In all three experiments, biochar was applied at three rates (0, 5, and …

Geochemical Tracers Of Holocene Environmental Change Along The East Antarctic Margin, Natalie Romanoff

Theses, Dissertations and Culminating Projects

Marine sediment geochemistry targeting both organic and inorganic compounds can be used for the reconstruction of paleoenvironmental conditions. Part 1 of this study was a qualitative organic geochemical analysis implemented on sediment cores from the Antarctic Peninsula (AP) and East Antarctic Margin (EAM). Intervals of organic or diatomaceous rich sediment were analyzed by Pyrolysis-Gas Chromatography/Mass Spectroscopy (Py-GC/MS) with the goal of identifying soft-bodied algae responsible for elevated wt% carbon levels in horizons where diatoms are absent, and identifying the presence of methanogens in basins where cold seeps are likely to be present. The identification of biomarkers in Antarctic sediment was …

Public School Science Education And Geographically-Specific Environmental Sustainability Issues: Implications For Social Work Education, Amanda Gallion

Mahurin Honors College Capstone Experience/Thesis Projects

The focus of this project was to examine the educational practices of Kentucky-based public school teachers (grades 4th-8th) related to their efforts to incorporate sustainability into the science classroom and specifically related to the teachers’ focus or lack of focus on karst landscape. The major themes that were analyzed were how educators include this content into their classroom material and how this impacts their students in the area of environmental sustainability. The themes analyzed were: environmental sustainability as a lifestyle choice; education about environmental sustainability, the nexus of family, school, and community; the importance of geographical context in regards to …

Volume Loss From Lower Peyto Glacier, Alberta, Canada, Between 1966 And 2010, Laura M. Kehrl, Robert L. Hawley, Erich C. Osterberg, Dominic A. Winski, Dominic A. Winski, Alexander P. Lee

Dartmouth Scholarship

Mass loss from mountain glaciers contributes to sea-level rise and reduces freshwater availability in glacier-fed river basins, with negative effects on hydropower generation, agriculture and the health of aquatic ecosystems. In this study, we determine the volume of lower Peyto Glacier, Alberta, Canada, from ground-penetrating radar surveys in 2008–10, and compare our volume estimate with previous estimates from 1966 and 1984. The long-term record of mass-balance estimates on Peyto Glacier highlights Peyto’s importance as an ‘index’ glacier for the region. We calculate a mean volume of (3.39 0.30) 10m for the glacier snout for the period 2008–10. Glacier volume decreased …

Water Quality Monitoring Protocol For Wadeable Streams And Rivers In The Northern Great Plains Network, Standard Operating Procedures Version 1.0, Marcia H. Wilson, Stephen K. Wilson

United States National Park Service: Publications

Executive Summary

The Water Quality Monitoring Protocol includes two parts: a Narrative and the Standard Operating Procedures (SOPs). The Water Quality Monitoring Protocol Narrative Version 1.0 describes a general overview of the status of water resources throughout the parks in the National Park Service’s Northern Great Plains Network (NGPN), the objectives, the field methods, and the sampling design selected for this long-term monitoring program. This report includes the detailed SOPs for the NGPN’s Water Quality Monitoring Protocol. All water quality monitoring is conducted by the United States Geological Survey (USGS) through Interagency Agreements. The USGS North Dakota Water Science Center …

Analysis, Toxicity, Occurrence And Biodegradation Of Nonylphenol Isomers: A Review, Zhijiang Lu, Jay Gan

Environmental Science and Geology Faculty Research Publications

Over the last two decades, nonylphenols (NPs) have become to be known as a priority hazardous substance due primarily to its estrogenicity and ubiquitous occurrence in the environment. Nonylphenols are commonly treated as a single compound in the evaluation of their environmental occurrence, fate and transport, treatment or toxicity. However, technical nonylphenols (tNPs) are in fact a mixture of more than 100 isomers and congeners. Recent studies showed that some of these isomers behaved significantly differently in occurrence, estrogenicity and biodegradability. The most estrogenic isomer was about 2 to 4 times more active than tNP. Moreover, the half lives of …

New Insights Into Skeletal Morphology Of The Oldest Known Silicoflagellates : Variramus, Cornua And Gleserocha Gen. Nov. = Nouvelles Connaissances Sur La Morphologie Du Squelette Des Plus Anciennes Silicoflagellés Connus : Variramus, Cornua Et Gleserocha Gen. Nov., Kevin Mccartney, Jakub Witkowski, David M. Harwood

ANDRILL Research and Publications

Two of the oldest known silicoflagellate-bearing sediments, lower Albian at Ocean Drilling Program Site 693 in the Weddell Sea of Antarctica and Santonian in the Devon Island sequence of the Canadian Archipelago, are re-examined with a focus on silicoflagellate genera Variramus, Cornua, and Gleserocha that lack basal rings, a feature appearing during late Santonian/early Campanian time within the genus Corbisema. The extraordinary variability of Variramus aculeifera is studied, and a new genus Gleserocha is proposed for taxa with apical structures made of three struts, but without pikes. This new genus includes previously described Variramus wisei and Cornua …

From The Depths Of Great Pond (Maine): Anthropogenic And Natural Influences On Bottom Sediments And The Implications For Local Sustainability, Sara George, Clara Bicher

CLAS: Colby Liberal Arts Symposium

As part of a Maine EPSCoR grant focusing on sustainability in the Belgrade Lakes watershed of central Maine, current research consists of collecting bottom sediment samples from Great Pond. Samples were analyzed to create a sediment map of the lake basin in regards to depth, grain-size distribution, organic content (%C), C:N ratios and phosphorus concentration. Results will aid in the understanding of the glacial formation of the lake, distribution of sediment within, and human impact on the lake. Additionally, knowing the distribution of phosphorus within the sediments may allow development of a strategy to avoid accelerated eutrophication. This research will …

Geothermobarometry Of Cordierite-Bearing Metapelites Of The Hudson Highlands, Southeastern Ny, Jay Patel

Theses, Dissertations and Culminating Projects

Various P-T determinations have been reported on metasedimentary rock suites in the New Jersey and Hudson Highlands using different geothermobarometers, but all have yielded relatively large P-T ranges and none have used cordierite in a quantitative way. The presence of variable cordierite and its narrow stability field in metapelitic gneisses provides an excellent opportunity to better constrain the peak P-T conditions. Calcium depleted, clay-rich, arkosic sedimentary protolith was deposited during the Mesoproterozoic in a continentaloceanic arc basin during the Elzevirian orogeny (~1300-1200 Ma). The Ottawan metamorphic event (~1090-1020 Ma) transformed this protolith into the metasedimentary unit exposed in the Hudson …

Watershed-Based Water Quality Management, Benjamin Barnett Witherell

Theses, Dissertations and Culminating Projects

In response to landscape alteration and increased knowledge of environmental systems, government regulation for the protection of water quality has undergone several adaptations since the landmark Clean Water Act of 1972. Most recently, in 2000, USEPA moved its emphasis from an effluent-based approach to an ambient or watershedbased approach. Prior watershed studies have uncovered relationships between the type of land cover in a watershed and water quality. These studies have generally indicated correlations between urbanized watersheds and degradation of water quality and aquatic ecosystem health. This dissertation is both an extension of these previous studies to the area of water …

Changes In The Discharge Characteristics Of The Hudson River, Elen Kenny Teo

Theses, Dissertations and Culminating Projects

The Hudson River watershed has undergone significant urbanization in some areas and reforestation in others during the past century. The watershed has also recently experienced extreme flood events, including from Hurricane Irene, which caused 49 deaths and an estimated $15.8 billion in damage nationally. However, it is unclear how much changes in land use and/or climate have caused shifts in river discharge and the contributions of runoff and baseflow to the river. Determining the existence and magnitude of these shifts are important for managing water resources. This study analyzes changes in daily flows and maximum annual discharge events at multiple …

Modeling Groundwater Flow At A Hydraulic Fracturing Site Near Pavillion, Wyoming, David Colombini

Theses, Dissertations and Culminating Projects

This thesis uses the GIS-conceptual model approach to create groundwater models investigating groundwater contamination near Pavillion, Wyoming. This area was part of a study by the US Environmental Protection Agency (EPA) in 2009 that claims domestic water well contamination originated from hydraulically fractured natural gas wells. Hydraulic fracturing is the process of injecting water, sand, and chemicals into gas and oil wells in order to stimulate well production. This has caused concern over groundwater contamination. The models show natural groundwater flow systems generally move from west to east, however, a recharge area near the center of the model locally disrupts …

Modeling A Green Decision Support System For Data Center Sustainability, Michael Joseph Pawlish

Theses, Dissertations and Culminating Projects

The objective of this dissertation is developing more energy efficient data centers while focusing on the environment as well as meeting the increasing computing needs. Reliability of data centers will be the number one priority for management; however, the focus will be to implement a design by incorporating free cooling, applying thermal profiling, utilizing data mining, and continuing virtualization to create more efficient green data centers that are good for the environment. Since the fall of 2009, electrical consumption patterns were measured in the main data center for the servers and the air-conditioners at Montclair State University (MSU) to quantify …

Understanding Selenium Distribution In Lake Mead Using A Three-Dimensional Hydrodynamic Based Water Quality Model, Xiaolu Wei

UNLV Theses, Dissertations, Professional Papers, and Capstones

Shallow groundwater and surface drainages in Las Vegas Wash are known to have elevated level of selenium which mainly comes from the naturally occurring geological hotspots on the southeast side of the Las Vegas Valley. Selenium fate and transport after it enters into Lake Mead from the Las Vegas Wash are not clearly understood. An open sourced three-dimensional Environmental Fluid Dynamic Code model (EFDC), developed by the United States Environmental Protection Agency, was used to model movement of selenium in the Boulder Basin, Lake Mead. The model was calibrated by observed data from 2006 to 2007. The concept of Lagrangian …

Finite Difference Modeling Of Surface-~Wave Scattering For Shallow Cavity Detection, Heston Travis Norcott

UNLV Theses, Dissertations, Professional Papers, and Capstones

Data collection and analysis of scattering of Rayleigh-type surface waves are investigated for locating shallowly buried cavities. Surface-based seismic experiments conducted by others at the University of Nevada, Las Vegas (UNLV) Engineering Geophysics Test Site (EGTS) demonstrate scattering of Rayleigh waves caused by buried empty barrels (essentially air-filled cavities). The interpretation of the data is complicated by factors such as the presence of a high-velocity geologic layer just below the cavity.

This research uses a finite-difference seismic wave propagation code to compute time histories for a model that represents the Engineering Geophysics Test Site. By adding cavities to a background …

Late Pliocene Ice-Rafted Debris Mass Accumulation Rates From Iodp Site U1359, Wilkes Land Continental Rise, Antarctica, Jessica Rosenberg

Theses, Dissertations and Culminating Projects

An assessment of sediments taken from the IODP (Integrated Ocean Drilling Program) Expedition 318, Core U1359A from the Wilkes Continental Land Rise, has been conducted at a high resolution to determine the response of the East Antarctic Ice Sheet to climate during the Late Pliocene. The section of core being studied dates back to ~3.7 to 2.7 million years ago (Ma). Studies can lead to an understanding of climate change in the future, from knowledge on how ice sheets have transformed in the past with similar atmospheric conditions to the present. Samples from this record were analyzed based on the …

Organic Geochemical Investigations Of Urban Sediments By Pyrolysis-Gas Chromatography / Mass Spectroscopy, Kevin Olsen

Theses, Dissertations and Culminating Projects

Pyrolysis-Gas Chromatography / Mass Spectrometry (Py-GC/MS) can be used to study the organic matter in sedimentary environments.

An urban sediment is not simply defined by proximity to a city. Because cities have anthropogenic contamination, one important urban sediment characteristic is ongoing recontamination. Another is legacy contamination from industrial activity and a third is the alteration of natural bio-geochemical systems.

Two case studies are presented. The surface sediments of the Gateway National Recreation Area were sampled during the summer of 2007. The ratio of two pyrolysis products, Vinylguiacol, from terrestrial plant lignins, and Indole, from proteins, (VGI Index) is moderately well …

Characterization Of Eocene-Oligocene Depocenters In Prydz Bay, East Antarctica : A Lithostratigraphic Correlation Of Odp Sites 739, 742, And 1166, Daniel James Ciarletta

Theses, Dissertations and Culminating Projects

The Eocene-Oligocene transition (EOT) marked a profound shift in the Earth’s climate, as the global greenhouse o f the early Cenozoic gave way to ‘icehouse’ conditions, or a climatic regime influenced by the waxing and waning o f glacial ice. Antarctica was dramatically altered during this time; its formerly cool temperate ecosystems nearly obliterated by the first major episode o f continental glaciation. A record o f this transition appears to be partly preserved in approximately half a kilometer o f sediments recovered from three holes (at ODP Sites 739, 742, and 1166) bored in the continental margin at Prydz …

Summer River Water Temperature Changes In The Musconetcong River And Their Potential Impact On Aquatic Habitat, Joseph Anthony Kowalski

Theses, Dissertations and Culminating Projects

Water temperature changes in rivers can happen quickly for multiple reasons, and can drastically impact the river in many ways. The potential for temperature shifts to impact rivers is especially important in the summer, for aquatic habitats, as the warm temperatures can stress populations. This is especially true for trout populations, a temperature-sensitive fish. Since temperature is the most important factor in the growth of trout, these temperature changes can be life threatening. Therefore it is important to monitor temperatures in the Musconetcong River, classified as trout maintenance waters (Musconetcong Advisory Committee et al., 2003), because of the potential negative …

The Effects Of Changes In Population Density On Discharges For The Midwestern United States, Catherine Konieczny

Theses, Dissertations and Culminating Projects

River baseflow is the river discharge supported predominantly by groundwater, and can be greatly impacted by changes in land. Intuitively, the baseflow of a river would decrease with increased urbanization, as urbanization increases the amount of impervious surfaces, limiting the ability of precipitation to infiltrate into the ground and recharge the local groundwater. However, evidence suggests that the baseflow of rivers in urbanized areas can increase as a result of leaky subsurface water infrastructures that add water to groundwater and replenish baseflow. Another reason for the baseflow increase in urbanized watersheds is that water supply systems are over-pressurized by design …