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Catalyzed Synthesis Of Zinc Clays By Prebiotic Central Metabolites, Ruixin Zhou, Kaustuv Basu, Hyman Hartman, Christopher J. Matocha, S. Kelly Sears, Hajatollah Vali, Marcelo I. Guzman 2017 University of Kentucky

Catalyzed Synthesis Of Zinc Clays By Prebiotic Central Metabolites, Ruixin Zhou, Kaustuv Basu, Hyman Hartman, Christopher J. Matocha, S. Kelly Sears, Hajatollah Vali, Marcelo I. Guzman

Chemistry Faculty Publications

How primordial metabolic networks such as the reverse tricarboxylic acid (rTCA) cycle and clay mineral catalysts coevolved remains a mystery in the puzzle to understand the origin of life. While prebiotic reactions from the rTCA cycle were accomplished via photochemistry on semiconductor minerals, the synthesis of clays was demonstrated at low temperature and ambient pressure catalyzed by oxalate. Herein, the crystallization of clay minerals is catalyzed by succinate, an example of a photoproduced intermediate from central metabolism. The experiments connect the synthesis of sauconite, a model for clay minerals, to prebiotic photochemistry. We report the temperature, pH, and concentration dependence ...


Mineralogy And Geochemistry Of The Heddleston Porphyry Cu-Mo Deposit, Montana, Ben Schubert 2017 Montana Tech

Mineralogy And Geochemistry Of The Heddleston Porphyry Cu-Mo Deposit, Montana, Ben Schubert

Graduate Theses & Non-Theses

The Heddleston porphyry Cu-Mo deposit is located in Lewis and Clark County, Montana, near the headwaters of the Blackfoot River. It is immediately west of the historic Mike Horse mine, an important producer of Pb-Zn from polymetallic veins and lodes. The Heddleston property was explored extensively by the Anaconda Company in the 1960s and 1970s, but was never mined. Specimens of polished drill core from the deposit are archived in the Anaconda Research Collection at Montana Tech campus. The purpose of this research project was to use the archived samples to examine the geochemistry and mineralogy of the Heddleston and ...


Supergene Mineralization Of The Continental Pit, Butte, Silver Bow County, Montana, Kyle Eastman 2017 Montana Tech

Supergene Mineralization Of The Continental Pit, Butte, Silver Bow County, Montana, Kyle Eastman

Graduate Theses & Non-Theses

The Butte porphyry Cu-Mo-Ag deposit has been considerably altered by supergene processes that enriched Cu and Ag, and mobilized other metals. Supergene enrichment provided early miners with excellent ore grades, and contributes significantly to current mining operations in Butte. The Continental Pit exhibits the classic leached and enriched vertical zonation that is common in near-surface porphyry systems around the world. Although studied by the Anaconda Copper Mining Company during the mid-20th century, significant and economically relevant questions remain regarding this deposit’s supergene heavy metal geochemistry and its relationship to the local hydrology and tectonic history.

This thesis investigates the ...


Cu-Pd Mineralization And Exploration Geochemistry Of The Eastern Gabbro, Coldwell Alkaline Complex, On, Canada, Yonghua Cao 2017 The University of Western Ontario

Cu-Pd Mineralization And Exploration Geochemistry Of The Eastern Gabbro, Coldwell Alkaline Complex, On, Canada, Yonghua Cao

Electronic Thesis and Dissertation Repository

The Eastern Gabbro forms the northern and eastern margin of the Coldwell Alkaline Complex. It contains three magma series: the barren meta-basalt, the Layered Series, and the Marathon Series which hosts all known PGE mineralization. The Marathon Series can be distinguished from other Series using the combination of portable X-ray fluorescence (pXRF) and benchtop scanning electron microscope (bSEM). Whole-rock Ba, Mg# (molar Mg/(Mg+Fe)*100), Zr and V/Ti values acquired from pXRF, and Mg#s of olivine and clinopyroxene, and anorthite content (molar Ca/(Ca+Na)*100) of plagioclase acquired from bSEM-EDS are key parameters. The Layered Series ...


Secondary Minerals From Salt Caves In The Atacama Desert (Chile): A Hyperarid And Hypersaline Environment With Potential Analogies To The Martian Subsurface, Jo De Waele, Cristina Carbone, Laura Sanna, Marco Vattano, Ermanno Galli, Francesco Sauro, Paolo Forti 2017 University of Bologna

Secondary Minerals From Salt Caves In The Atacama Desert (Chile): A Hyperarid And Hypersaline Environment With Potential Analogies To The Martian Subsurface, Jo De Waele, Cristina Carbone, Laura Sanna, Marco Vattano, Ermanno Galli, Francesco Sauro, Paolo Forti

International Journal of Speleology

Over the past 15 years several expeditions by French, American and especially Italian cavers have unveiled over 50 caves in the Cordillera de la Sal (Atacama Desert, Northern Chile). Many of these caves contain a variety of speleothems and minerals, some of which have rarely been observed within karst systems. Most of the secondary deposits in these caves are composed of halite, but also other halide, carbonate, sulphate, nitrate, phosphate, and silicate minerals have been found. Among the sixteen cave mineral species recognized, atacamite, darapskite, blödite, leonite, anhydrite, and especially antarcticite are worth mentioning. In one of the samples an ...


Petrographical And Geochemical Changes In Bosnian Stalagmites And Their Palaeo-Environmental Significance, Veronica Chiarini, Isabelle Couchoud, Russell Drysdale, Petra Bajo, Simone Milanolo, Silvia Frisia, Alan Greig, John Hellstrom, Jo De Waele 2017 University of Bologna

Petrographical And Geochemical Changes In Bosnian Stalagmites And Their Palaeo-Environmental Significance, Veronica Chiarini, Isabelle Couchoud, Russell Drysdale, Petra Bajo, Simone Milanolo, Silvia Frisia, Alan Greig, John Hellstrom, Jo De Waele

International Journal of Speleology

Detailed petrographic observations have been coupled with trace element and δ13C - δ18O analyses in order to investigate their dynamics in two Holocene Bosnian speleothems. The potential of this multiproxy approach in providing a means to extract palaeo-environmental information from stalagmites whose stable isotope signals are noisy and without obvious trends has been tested. The studied stalagmites are mostly characterized by columnar microcrystalline fabric. At the sub-millimetre scale of lamination, different microcrystalline columnar sub-types (open and closed) have been detected and classified on the basis of the observed porosity and the crystallite size. The presence of variations ...


Effects Of Nonaerated Circulation Water Velocity On Nutrient Release From Aquaculture Pond Sediments, Xiangju Cheng, Dantong Zhu, XiXi Wang, Deguang Yu, Jun Xie 2017 Old Dominion University

Effects Of Nonaerated Circulation Water Velocity On Nutrient Release From Aquaculture Pond Sediments, Xiangju Cheng, Dantong Zhu, Xixi Wang, Deguang Yu, Jun Xie

Civil & Environmental Engineering Faculty Publications

Sustaining good water quality in aquaculture ponds is vital. Without an aerator, the dissolved oxygen in ponds comes primarily from mass transfer at the water-ambient atmosphere interface. As sediment can seriously affect water quality, this study used indoor experiments to examine the nutrient (nitrogen and phosphorus) release mechanisms and fluxes from sediment in aquaculture ponds with moving water but no aeration. The results showed that the ammonia nitrogen (NH3-N) concentration in the overlying water was inversely proportional to flow velocity and that a higher flow velocity tended to result in a lower concentration in the overlying water, a ...


Mercury Increases In Lake Tanganyika Since ~1850, Troy A. Bole 2017 The University of Akron

Mercury Increases In Lake Tanganyika Since ~1850, Troy A. Bole

Honors Research Projects

A series of three sediment cores were collected in Lake Tanganyika, Africa, and were analyzed for mercury concentrations. For all three cores, a decrease in mercury (Hg) levels was observed from the 1600’s (appx. 20 ng/g) until concentrations reached a minimum during the mid-1800’s (appx. 10 ng/g). The mid-1800’s marked a change from decreasing mercury levels to an increase over the following century. The core tops (circa 2006) have concentrations greater than 70 ng/g. The onset of the rise in mercury concentrations coincides with the beginning of the Industrial Revolution in the mid to ...


Hydrocarbon And Co2 Emissions From Oil And Gas Production Well Pad Soils Comparative To Background Soil Emissions In Eastern Utah, Cody S. Watkins 2017 Utah State University

Hydrocarbon And Co2 Emissions From Oil And Gas Production Well Pad Soils Comparative To Background Soil Emissions In Eastern Utah, Cody S. Watkins

All Graduate Theses and Dissertations

Emissions of methane, non-methane hydrocarbons (NMHC), and carbon dioxide (CO2) at 27 natural gas well pads, 11 non-well locations in oil and gas fields, and 7 hydrocarbon-bearing outcrops in eastern Utah between 2013 and 2016 were measured using a dynamic flux chamber (DFC) in effort to answer the following questions: What effect does the development of oil and gas have on the observed air quality (increased ozone, CO2, volatile organic compounds (VOCs), and/or methane emissions) in northeastern Utah? What percentage of these gases is due to natural background emissions, and what percentage is due to oil and ...


Zircon As A Proxy For "Taking The Temperature" Of Granites: An Example Using Zircon Thermometry Applied To Grenvillian Mid-Crustal Magmas In The Blue Ridge Province, Virginia, Samantha Rae Burk 2017 University of Kentucky

Zircon As A Proxy For "Taking The Temperature" Of Granites: An Example Using Zircon Thermometry Applied To Grenvillian Mid-Crustal Magmas In The Blue Ridge Province, Virginia, Samantha Rae Burk

Theses and Dissertations--Earth and Environmental Sciences

The Grenville orogeny was a protracted (~200 m.y.) series of “hot” magmatic- metamorphic events that contributed to the growth of the Laurentian margin in the late Mesoproterozoic. The granites contain remarkably high Zr content, lack xenocrysts, and become zircon saturated at high temperatures, which are all unusual for felsic magmas. The “hot Grenville granite” hypothesis is tested and use of high-Zr granitoids as potential zones of crustal magma generation through: U-Pb geochronology and cathodoluminescence imaging to assess inherited zircon components; quantitative modeling of zircon crystallization history using rhyolite-MELTS; and Ti-in-zircon thermometry. U-Pb zircon ages for two samples from the ...


An Investigation Of Paleo-Wildfires During The Cretaceous-Paleogene (K-Pg) Boundary At El Kef, Tunisia, Michael Gross 2017 University of Colorado, Boulder

An Investigation Of Paleo-Wildfires During The Cretaceous-Paleogene (K-Pg) Boundary At El Kef, Tunisia, Michael Gross

Undergraduate Honors Theses

The causes and consequences of the Cretaceous-Paleogene mass extinction have long been a source of contention. Several models predict that enough thermal radiation from the bolide impact was produced to ignite wildfires at least regionally and possibly on a global scale, raising average temperatures by up to ~10°C, and releasing large amounts of CO2 and CO. However, the role of regional versus global wildfire events as an environmental stressor, as well as the sources of the fire (land vegetation vs. hydrocarbon reservoirs) and its expression in terrestrial and marine archives, remains controversial. Typically, wildfires are preserved in the ...


Sedimentology And Geochemistry Of The Mixed Carbonate-Siliciclastic Espanola Formation, Paleoproterozoic Huronian Supergroup, Bruce Mines-Elliot Lake Area, Ontario, Canada, Mansour H. Al-Hashim 2016 The University of Western Ontario

Sedimentology And Geochemistry Of The Mixed Carbonate-Siliciclastic Espanola Formation, Paleoproterozoic Huronian Supergroup, Bruce Mines-Elliot Lake Area, Ontario, Canada, Mansour H. Al-Hashim

Electronic Thesis and Dissertation Repository

The Espanola Formation of the Paleoproterozoic Huronian Supergroup is a mixed carbonate-siliciclastic succession. Detailed sedimentological analysis of the formation in the Bruce Mines-Elliot Lake region reveals 17 sedimentary lithofacies, which comprise three distinct lithofacies associations. The lithofacies associations represent, in ascending order, shoreface, offshore, and nearshore (or lagoon) depositional environments along a wave- and storm-dominated shallow siliciclastic marine shelf. Major, trace, and rare earth element analyses of the siliciclastic component indicate derivation from a mainly granodioritic Archean upper continental crust with some contributions from mafic volcanic and/or sedimentary rocks. The results show that the source rocks were subjected to ...


Characterizing Crystal Populations For The Petrogenesis Of The Post-Collapse Rhyolites In The Long Valley Caldera, California, William Joseph 2016 University of Nevada, Las Vegas

Characterizing Crystal Populations For The Petrogenesis Of The Post-Collapse Rhyolites In The Long Valley Caldera, California, William Joseph

UNLV Theses, Dissertations, Professional Papers, and Capstones

Post-collapse rhyolites of the Long Valley in eastern California are the product of remelting of crystal mush bodies via mafic rejuvenation following the eruption of the Bishop Tuff. This is supported by mineral textures and major element geochemistry from the Resurgent Dome rhyolite, the Moat rhyolite, the Hot Creek Flow, and the Deer Mountain rhyolite. New 40Ar/39Ar eruptive ages are reported for the Moat rhyolites (525 ka, 333 ka, 118 – 94 ka), Hot Creek Flow (312 – 295 ka), and the Deer Mountain rhyolite (65 ka). The initial post-collapse eruptions, resulting in the Resurgent Dome rhyolite, appear to be derived ...


Temporal Co2 Variations And The Influence Of Bat Colonies In Speleogenesis: Continuous Co2 Monitoring In War Eagle Cavern, Arkansas, Ginny Sue Holcomb 2016 University of Arkansas, Fayetteville

Temporal Co2 Variations And The Influence Of Bat Colonies In Speleogenesis: Continuous Co2 Monitoring In War Eagle Cavern, Arkansas, Ginny Sue Holcomb

Theses and Dissertations

Dissolved concentrations of CO2 in a karst aquifer are a major control on calcite dissolutional processes, as CO2 combines chemically with water to form carbonic acid. As increasing amounts of CO2 are added to the system, greater resultant water aggressivity generates greater rates of dissolution. Spatial and temporal variations in carbon flux through the system may occur over a range of time scales, and high-resolution data collection is needed to truly understand and characterize such variability. Continuous CO2 monitoring in War Eagle Cavern, Arkansas, will suggest a number of influential parameters with varying degrees of importance throughout an annual cycle ...


Abrupt Ocean Anoxia During The Late Ordovician Mass Extinction Detected Using Uranium Isotopes Of Marine Carbonates, Rickey Bartlett, Maya Elrick, Yemane Asmerom, Viorel Atudorei 2016 University of New Mexico

Abrupt Ocean Anoxia During The Late Ordovician Mass Extinction Detected Using Uranium Isotopes Of Marine Carbonates, Rickey Bartlett, Maya Elrick, Yemane Asmerom, Viorel Atudorei

Earth and Planetary Sciences ETDs

The Ordovician witnessed an explosion in marine biodiversity punctuated by the first of the ‘big-5’ Phanerozoic mass extinctions, the Late Ordovician mass extinction (LOME). The LOME consists of two discrete pulses occurring at the beginning and end of the Hirnantian. Lithologic and geochemical evidence suggests widespread marine anoxia triggered the second LOME pulse; however, most of these redox proxies record local bottom water or porewater conditions rather than global seawater conditions. To evaluate global redox trends, we utilize uranium (U) isotopes and trace element geochemistry of marine carbonates as a global marine redox proxy.

Bulk carbonate samples were collected from ...


A Stable Isotope Investigation Of Pollen From Pinery Provincial Park, Southwestern Ontario, Canada, Deana M. Schwarz 2016 The University of Western Ontario

A Stable Isotope Investigation Of Pollen From Pinery Provincial Park, Southwestern Ontario, Canada, Deana M. Schwarz

Electronic Thesis and Dissertation Repository

Pollen is a useful proxy for reconstructing paleoclimate; however, the relationship between its stable isotopic composition and the environment in which it forms is still poorly understood. We examine the stable oxygen, carbon, and nitrogen isotope compositions of pollen from tree (coniferous and deciduous), grass (C3 and C4), and marsh species from Pinery Provincial Park, Ontario, and its environs, and maple and oak tree species from eight localities across the United States of America, to (i) determine the major environmental influences on pollen δ18O, δ13C, and δ15N values, (ii) examine the causes ...


Abundance Of Archaias Angulatus On The West Florida Coast Indicates The Influence Of Carbonate Alkalinity Over Salinity, Sean Thomas Beckwith 2016 University of South Florida

Abundance Of Archaias Angulatus On The West Florida Coast Indicates The Influence Of Carbonate Alkalinity Over Salinity, Sean Thomas Beckwith

Graduate Theses and Dissertations

Archaias angulatus, a large symbiont-bearing foraminifer (Order Miliolida) that produces a Mg-calcite shell, is common throughout the Caribbean and warm western Atlantic region. This species lives abundantly in seagrass beds along the Springs Coast of northwest Florida (up to 4 adults per gram of sediment) where spring-fed rivers emerge from a limestone aquifer, and in Florida Bay to the southeast (25 adults/g) where the sediment is primarily biogenic carbonate. In contrast, live specimens are seldom found in the seagrass beds along the central-west coast of Florida, where barrier islands are dominated by quartz sand. My working hypothesis is that ...


The Character And Distribution Of Cu-Pge Mineralization At The Geordie Lake Deposit Within The Coldwell Complex, Ontario, Imran Meghji 2016 The University of Western Ontario

The Character And Distribution Of Cu-Pge Mineralization At The Geordie Lake Deposit Within The Coldwell Complex, Ontario, Imran Meghji

Electronic Thesis and Dissertation Repository

Cu-PGE mineralization at the Geordie Lake Deposit (GLD) is spatially associated with weak to intense actinolite and albite alteration within gabbro and troctolite. Previous studies have determined a magmatic, and magmatic-hydrothermal origin of the deposit. The most significant Cu-PGE occurrence in the GLD is dominantly stratiform, and in contact with a basal syenite. Similar patterns of REE with progressive enrichment from troctolite, to gabbro, and basal syenite indicate that these lithologies are genetically linked. Major element geochemistry shows no discernable variation between the altered and unaltered samples. Whole rock δ18O analyses were conducted in equal intervals down the ...


Surficial Geology Of York College Campus (Queens) And Montauk Point (Long Island): An Open Access To Geoscience Education, Nazrul I. Khandaker, Stanley Schleifer, Krishna Mahabir, Erik Menjivar, Ality Aghedo, Dennis Baidoo, Tenzin Choeying, Vanessa Erwin, Jonathan Xavier, Laboni Molla, Akeed Alrubay 2016 CUNY York College

Surficial Geology Of York College Campus (Queens) And Montauk Point (Long Island): An Open Access To Geoscience Education, Nazrul I. Khandaker, Stanley Schleifer, Krishna Mahabir, Erik Menjivar, Ality Aghedo, Dennis Baidoo, Tenzin Choeying, Vanessa Erwin, Jonathan Xavier, Laboni Molla, Akeed Alrubay

Publications and Research

To evaluate compositional and textural differences among the samples collected from York College (YC) campus (Queens), Montauk Point (MP) and Hither Hills (HH), Long Island, emphasis is given to the general geologic setting, overall grain size distribution, and relative abundances of light and heavy mineral assemblages. Geologic setting encompasses outwash plains (York College), fluvioglacial and glacial (Montauk Point) and beach and dune complex (Hither Hills). YC samples were collected from depth ranging 40 cm to 250 cm and are mostly an assortment of medium to coarse sand, granule to cobble sized, minor silt, and clay. Presence of low angle cross ...


Convergence In Nitrogen Deposition And Cryptic Isotopic Variation Across Urban And Agricultural Valleys In Northern Utah, Steven J. Hall, E. M. Ogata, S. R. Weintraub, M. A. Baker, J. R. Ehleringer, C. I. Czimczik, D. R. Bowling 2016 Iowa State University

Convergence In Nitrogen Deposition And Cryptic Isotopic Variation Across Urban And Agricultural Valleys In Northern Utah, Steven J. Hall, E. M. Ogata, S. R. Weintraub, M. A. Baker, J. R. Ehleringer, C. I. Czimczik, D. R. Bowling

Ecology, Evolution and Organismal Biology Publications

The extent to which atmospheric nitrogen (N) deposition reflects land use differences and biogenic versus fossil fuel reactive N sources remains unclear yet represents a critical uncertainty in ecosystem N budgets. We compared N concentrations and isotopes in precipitation-event bulk (wet + dry) deposition across nearby valleys in northern Utah with contrasting land use (highly urban versus intensive agriculture/low-density urban). We predicted greater nitrate (NO3−) versus ammonium (NH4+) and higher δ15N of NO3− and NH4+ in urban valley sites. Contrary to expectations, annual N deposition (3.5–5.1 kg N ha−1 yr−1) and inorganic N concentrations were ...


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