Multivariate Spectral Analysis Of Crism Data To Characterize The Composition Of Mawrth Vallis, 2018 Wesleyan University
Multivariate Spectral Analysis Of Crism Data To Characterize The Composition Of Mawrth Vallis, Melissa Luna
No abstract provided.
Iron Isotope Fractionation During Fe(Ii) Oxidation Mediated By The Oxygen-Producing Marine Cyanobacterium Synechococcus Pcc 7002, Elizabeth S. Swanner, Timm Bayer, Wenfang Wu, Likai Hao, Martin Obst, Anneli Sundman, James Martin Byrne, F. M. Michel, I. C. Kleinhanns, A. Klapper, R. Schoenberg
Elizabeth D. Swanner
In this study, we couple iron isotope analysis to microscopic and mineralogical investigation of iron speciation during circumneutral Fe(II) oxidation and Fe(III) precipitation with photosynthetically produced oxygen. In the presence of the cyanobacterium Synechococcus PCC 7002, aqueous Fe(II) (Fe(II)aq) is oxidized and precipitated as amorphous Fe(III) oxyhydroxide minerals (iron precipitates, Feppt), with distinct isotopic fractionation (ε56Fe) values determined from fitting the δ56Fe(II)aq (1.79‰ and 2.15‰) and the δ56Feppt (2.44‰ and 2.98‰) data trends from two replicate experiments. Additional Fe(II) and Fe(III) phases were detected using microscopy ...
Geophysical Delineation Of Megaporosity And Fluid Migration Pathways For Geohazard Characterization Within The Delaware Basin, Culberson County, Texas, 2017 Stephen F. Austin State University
Geophysical Delineation Of Megaporosity And Fluid Migration Pathways For Geohazard Characterization Within The Delaware Basin, Culberson County, Texas, Jonathan David Woodard
Electronic Theses and Dissertations
Differential dissolution of gypsum karst within the Delaware Basin poses a significant threat to infrastructure that society depends on. The study area is located in Culberson County, Texas and traverses a distance of approximately 54 kilometers along RM 652 within the Gypsum Plain which is situated on the northern margin of the Chihuahua Desert and includes outcrops of Castile and Rustler strata that host karst geohazards. Regions of karst geohazard potential have been physically surveyed proximal to the study area in evaporites throughout the Castile Formation outcrop; minimal hazards, in comparison to the Castile Formation, have been documented in ...
Further Study Of Garnet Xenocrysts In New York City Migmatites, 2017 York College CUNY
Further Study Of Garnet Xenocrysts In New York City Migmatites, Stanley Schleifer, Nazrul I. Khandaker
Publications and Research
The authors have previously published an article at the 2004 Geological Society of America Annual Meeting, Petrogenetic Significance of Garnets in the Bedrock of New York City, in which they suggested that the garnet xenocrysts observed in the quartzofeldspathic zones of the migmatites, so frequently seen both at the surface, and below the surface pursuant to the construction of the Manhattan portion of New york City Water Tunnel #3, were a refractory residue of the anatectic melting of the immediately surrounding schistose bedrock. Although the relatively high melting point temperature of garnet compared to other minerals in the surrounding schists ...
Annually Resolved North Atlantic Marine Climate Over The Last Millennium, 2017 Cardiff University
Annually Resolved North Atlantic Marine Climate Over The Last Millennium, D. J. Reynolds, J. D. Scourse, P. R. Halloran, A. J. Nederbragt, Alan D. Wanamaker, P. G. Butler, C. A. Richardson, J. Heinemeier, J. Eiriksson, K. L. Knudsen, I. R. Hall
Owing to the lack of absolutely dated oceanographic information before the modern instrumental period, there is currently significant debate as to the role played by North Atlantic Ocean dynamics in previous climate transitions (for example, Medieval Climate Anomaly-Little Ice Age, MCA-LIA). Here we present analyses of a millennial-length, annually resolved and absolutely dated marine δ18O archive. We interpret our record of oxygen isotope ratios from the shells of the long-lived marine bivalve Arctica islandica (δ18O-shell), from the North Icelandic shelf, in relation to seawater density variability and demonstrate that solar and volcanic forcing coupled with ocean circulation dynamics are key ...
Depositional And Environmental Controls On Oxygen And Carbon Isotope Compositions Of Late Pleistocene To Mid-Holocene Shelly Fauna From The Huron Basin, Ontario, Canada, 2017 The University of Western Ontario
Depositional And Environmental Controls On Oxygen And Carbon Isotope Compositions Of Late Pleistocene To Mid-Holocene Shelly Fauna From The Huron Basin, Ontario, Canada, Jane Wilson
Electronic Thesis and Dissertation Repository
The δ¹⁸O and δ¹³C of aragonitic mollusc shells were analyzed from nine sites in the Huron Basin, Ontario, Canada. These sites represent three lake phases spanning the Late Pleistocene to the mid-Holocene (Algonquin, Transitional, and Nipissing) and three depositional environments (fluvial, estuarine, and lacustrine). Depositional environment controls mollusc δ¹⁸O more strongly than climate. The source of carbon and climate control the δ¹³C of the shelly fauna. Shells from fluvial sites are most depleted of ¹⁸O and exhibit the greatest antipathetic δ¹³C-δ¹⁸O covariation. This reflects the dynamic nature of this system. Lacustrine sites have ...
Quality Assurance Of Co2 From Natural Gas Source For The Spruce Experiment, 2017 California Polytechnic State University, San Luis Obispo
Quality Assurance Of Co2 From Natural Gas Source For The Spruce Experiment, Kimberly Arias, Karis J. Mcfarlane, Alexandra Hedgpeth
STAR (STEM Teacher and Researcher) Presentations
The goal of the Spruce and Peatland Responses Under Changing Environments (SPRUCE) experiment project, led by Oak Ridge National Laboratory (ORNL), is to observe and assess ecological responses of peatland ecosystems to increased temperatures and elevated atmospheric CO2 concentrations. Control plots are maintained at ambient temperatures and/or CO2 concentrations. Treatments are applied in a full factorial design; plots are warmed to +2.25, +4.5, +6.75, and +9oC and exposed to an atmospheric CO2 concentration of 800 to 900 ppm. These parameters are set to reflect projected temperatures and atmospheric CO2 levels in the next century. The source ...
The Dynamic Relationship Between The Bear River, Quaternary Basaltic Center, Normal Faults, And The Resulting Rearrangement Of Rivers In The Northeast Edge Of The Great Basin, Southeast Idaho, 2017 Utah State University
The Dynamic Relationship Between The Bear River, Quaternary Basaltic Center, Normal Faults, And The Resulting Rearrangement Of Rivers In The Northeast Edge Of The Great Basin, Southeast Idaho, Brady Utley
All Graduate Plan B and other Reports
The objective of this research project in Gem Valley graben, southeast Idaho is to identify the location, age and history of the Quaternary diversion of the Bear River into paleo-Lake Thatcher, and then into the Lake Bonneville basin from the Columbia River basin. Mapping, geochemical analysis, cross-cutting relationships, and five new age determinations, together with prior published research, shed new light on the complex history of interaction between the volcanic rocks, rivers, lakes, and faults in Gem Valley. Research goals were to test the hypothesis that local faulting and volcanism drove the diversion of the Bear River and controlled the ...
Urban Detention Basin Contamination With Polycyclic Aromatic Hydrocarbons (Pahs) And Metals, 2017 Missouri State University
Urban Detention Basin Contamination With Polycyclic Aromatic Hydrocarbons (Pahs) And Metals, Holly Marie Duff
MSU Graduate Theses
Polycyclic aromatic hydrocarbons (PAHs) are organic compounds that can be toxic to wildlife and humans when released to the environment. Coal-tar sealants, which are applied to parking lots or driveways, contribute up to 1,000 times more PAHs than alternative sealants. Over time, these sealants abrade and are transported into drainage networks. Coal-tar sealants are currently used in Springfield, Missouri, however the extent of PAH contamination throughout urban drainage systems is unclear. This study focused on PAH contamination within an urban detention basin on the Missouri State University campus which receives runoff from several coal-tar sealed parking lots. Sediment samples ...
New Biotite And Muscovite Isotopic Reference Materials, Usgs57 And Usgs58, For Δ2h Measurements–A Replacement For Nbs 30, Haiping Qi, Tyler B. Coplen, Matthias Gehre, Torsten W. Vennemann, Willi A. Brand, Heike Geilmann, Gerald Olack, Ilya N. Bindeman, Jim Palandri, Li Huang, Fred J. Longstaffe
Earth Sciences Publications
The advent of continuous-flow isotope-ratio mass spectrometry (CF-IRMS) coupled with a high temperature conversion (HTC) system enabled faster, more cost effective, and more precise δ2H analysis of hydrogen-bearing solids. Accurate hydrogen isotopic analysis by on-line or off-line techniques requires appropriate isotopic reference materials (RMs). A strategy of two-point calibrations spanning δ2H range of the unknowns using two RMs is recommended. Unfortunately, the supply of the previously widely used isotopic RM, NBS 30 biotite, is exhausted. In addition, recent measurements have shown that the determination of δ2H values of NBS 30 biotite on the VSMOW-SLAP ...
Field Occurrence, Chemical Composition And Industrial Application Of Ekinrin-Adde Marble Deposit, Kogi State, North Central Nigeria, 2017 Kogi State University, Anyigba
Field Occurrence, Chemical Composition And Industrial Application Of Ekinrin-Adde Marble Deposit, Kogi State, North Central Nigeria, M Onimisi, I T. Ojonimi, M S. Kolawole, T B. Ibimode
Confluence Journal of Environmental Studies (CJES), Kogi State University, Nigeria
Enstatite Achondrites As Indicators Of Processes And Environments In The Early Solar System, 2017 The University of Western Ontario
Enstatite Achondrites As Indicators Of Processes And Environments In The Early Solar System, Diego David Uribe
Electronic Thesis and Dissertation Repository
This thesis investigates the processes and environments of formation of the anomalous enstatite achondrites NWA 4301, Zakłodzie, and NWA 8173 to determine how they relate to other enstatite meteorites (chondrites, impact melt rocks, aubrites, and so-called “primitive enstatite achondrites”). Observations of Zakłodzie and NWA 4301 showed both meteorites may share a common parent body, but experienced different metamorphic conditions. Different zonation patterns in plagioclase, silica polymorphs and associations, and sulfide assemblages indicate Zakłodzie experienced higher metamorphic temperatures and cooled faster than NWA 4301, therefore NWA 4301 was buried deeper in the parent body relative to Zakłodzie. In NWA 8173, mineral ...
Sedimentary Characteristics And Nutrient Sequestration Of Embanked Floodplains Along The Lower Mississippi River, Mississippi And Louisiana, 2017 The University of Southern Mississippi
Sedimentary Characteristics And Nutrient Sequestration Of Embanked Floodplains Along The Lower Mississippi River, Mississippi And Louisiana, R M Malitha Chanuka Bandara Rathnayake
The Mississippi River Basin is the largest river basin in North America and the third largest river basin in the world. Most of the corn, soybeans, wheat, cattle, and hogs harvested in the United States come from the Mississippi River Basin and about 58% of the entire drainage basin is croplands. Runoff from these lands carries sediments and nutrients, and the Mississippi River transports these downstream and ultimately deposits them in the Gulf of Mexico. The northern Gulf of Mexico is one of largest human-caused hypoxic zones in the world. Hypoxia is the phenomena where the dissolved oxygen level decreases ...
Measuring Inorganic Carbon Fluxes From Carbonate Mineral Weathering From Large River Basins: The Ohio River Basin, 2017 Western Kentucky University
Measuring Inorganic Carbon Fluxes From Carbonate Mineral Weathering From Large River Basins: The Ohio River Basin, Autumn B. Turner
Masters Theses & Specialist Projects
Rising atmospheric CO2 concentrations have motivated efforts to better quantify reservoirs and fluxes of Earth’s carbon. Of these fluxes from the atmosphere, one that has received relatively little attention is the atmospheric carbon sink associated with carbonate mineral dissolution. Osterhoudt (2014) and Salley (2016) explored new normalization techniques to improve and standardize a process for measuring this flux over large river basins. The present research extends this work to the 490,600 km2 Ohio River drainage basin and 11 subbasins. The study estimated the DIC flux leaving these basins between October 1, 2013, and September 30, 2014, based on ...
Nuclear Weapons In A Changing Climate: Probability, Increasing Risks, And Perception, 2017 University of Nebraska - Lincoln
Nuclear Weapons In A Changing Climate: Probability, Increasing Risks, And Perception, Adam Liska, Tyler R. White, Eric Holley, Robert J. Oglesby
Adam Liska Papers
Many people tend to think that the outcome of any nuclear weapons use today will result in an escalatory situation with apocalyptic outcomes for the countries involved. Yet many factors are increasing the probability of the limited use of nuclear weapons (e.g., 1 to 20 warheads) in a range of conflict scenarios. Previous atmospheric model simulations of regional nuclear conflicts employing many relatively small bombs have been estimated to cause a global “nuclear autumn,” with great reductions in agricultural productivity, stratospheric ozone loss, and spread of hazardous radioactive fallout. The totality of these effects would result in widespread ...
Biogeochemical Interactions In Flooded Underground Mines, 2017 Montana Tech
Biogeochemical Interactions In Flooded Underground Mines, Renee Schmidt
Graduate Theses & Non-Theses
This study presents a biogeochemical analysis of microbial communities in flooded underground mines in Butte, Montana, USA. Samples were collected from nine mineshafts representing three distinct geochemical zones. These zones consist of the East, West, and Outer Camp mines. The East Camp mines, bordering the Berkeley Pit Superfund site, have the highest concentrations of dissolved metals and the most acidic pH values. Dissolved metal concentrations in the West Camp are one to three orders of magnitude lower than in the East Camp and have nearly neutral pH values. The Outer Camp mines have similar metal concentrations to the West Camp ...
Foundations For A Geobiochemical Characterization Of Mudpots In Yellowstone National Park, Georgia Dahlquist
Graduate Theses & Non-Theses
Mudpots are acidic, turbid thermal features formed by the argillic or sericitic alteration of rock with enough fluid to create a viscous feature. Prior to this research, the combination of interdisciplinary sampling for geochemistry, mineralogy, and microbiology of rhyolite hosted mudpots, particularly in chemically distinct subregions of an area, remained largely unavailable. This work discusses mudpots and nearby hot springs sampled in Yellowstone National Park (YNP) in July 2016 and the measured in situ pH, temperature, and conductivity values, and dissolved oxygen concentrations. Water, filtered via gravity pre-filtration and 1.2 μm and 0.8/0.2μm syringe filtration, yielded ...
Tracking Potential Leakage Of Tailings-Lake Water Into Background Groundwater In Butte, Montana, Using Geochemical And Stable Isotope Tracers, Matthew Berzel
Graduate Theses & Non-Theses
This study was conducted to identify environmental tracers using water chemistry and stable isotopes in the Moulton Road area adjacent to the Yankee Doodle tailings impoundment north of Butte, Montana. The water level of the tailings lake is being raised as tailings slurry is pumped up to the impoundment, and numerous residential wells are located in close proximity. Although it has an alkaline pH (> 9), the water in the tailings lake is much higher in some chemical constituents than the wells and some of these constituents could be used as tracers to determine if lake water is migrating out of ...
Comprehensive Silica Removal With Ferric Compounds For Industrial Wastewater Reuse, 2017 University of New Mexico
Comprehensive Silica Removal With Ferric Compounds For Industrial Wastewater Reuse, Ehren D. Baca
Civil Engineering ETDs
Cooling towers, integrated circuit (IC) manufacture and reverse osmosis (RO) generate copious amounts of wastewater high in colloidal and reactive silica inhibiting on-site or synergistic reuse. Silica present in cooling water can reach solubility limits via evaporation and form impervious scale on heat transfer surfaces that decreases efficiency. When water is treated by RO operating at high rejection, silica forms difficult-to-remove scale on the membrane feed side in the form of glassy patches and communities of aggregate particles, inhibiting aspirations for zero liquid discharge. Current methods for silica scale mitigation include abundant dosing with chemical antiscalents or complex operating schemes ...
The Effect Of Diffusive Transport On Mineral Carbonation In Geologic Carbon Sequestration, 2017 Washington University in St Louis
The Effect Of Diffusive Transport On Mineral Carbonation In Geologic Carbon Sequestration, Wei Xiong
Engineering and Applied Science Theses & Dissertations
Geologic carbon sequestration (GCS) is an effective method to mitigate environmental problems due to excessive anthropogenic CO2 emissions. It involves injecting supercritical CO2 into deep geologic formations in which CO2 will ultimately be converted to solid carbonate minerals. Basalt is a promising host rock that is rich in the divalent cations Ca, Mg and Fe that are important for mineral trapping of CO2. Fractures and pores in basalt reservoirs provide substantial surface area for geochemical reactions during carbon sequestration. The transport in fractures and pores is controlled by diffusion. The coupling of diffusive transport and geochemical reactions leads to carbonate ...