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The Impact Of Burning On The Structure And Mineral Composition Of Bat Guano, Joyce Lundberg, Donald A. McFarlane 2021 Carleton University, Ottawa, Canada

The Impact Of Burning On The Structure And Mineral Composition Of Bat Guano, Joyce Lundberg, Donald A. Mcfarlane

International Journal of Speleology

Here we addressed the question of whether burning of guano produces a characteristic suite of morphological changes and/or unique mineralogical products. The changes observed in our experimental burning of guano (both fresh and decayed) included colour change (blackening), grain size and morphological change (grain size generally reduced, morphology rendered generally less distinct), alteration of minerals by dehydration (e.g., gypsum to anhydrite, brushite to whitlockite), and production of new minerals or compounds (e.g., augelite, bayerite, giniite, graphite, oldhamite, strontium apatite, tridymite). The key morphological feature we found that may be diagnostic of burning was severe damage to crystals from rapid dehydration …


Carbonate Paleothermometry In Fayetteville Green Lake, New York, Micah Wiesner 2021 Syracuse University

Carbonate Paleothermometry In Fayetteville Green Lake, New York, Micah Wiesner

Theses - ALL

Lacustrine carbonates are important paleoclimate archives, but unknowns in the seasonal timing and depth of precipitation obscure the interpretation of temperatures associated with them. The clumped isotope paleothermometer records the formation temperature T(D47) of carbonates. This study examines a set of lacustrine carbonates formed in the water column, in addition to carbonate from a sediment core, to better understand the depth and seasonality of carbonate formation in a lacustrine setting. We test that, regardless of season and formation temperature, lacustrine carbonates form in isotopic equilibrium with respect to D47 and d18O fractionation. Further, we account for the effect of our …


Mesoproterozoic Basement From The Central And Southern Appalachians Reveal High-Temperature Magmatic Conditions And Non-Laurentian Origin Of Earth's Most Zircon Fertile Magmas, Kyle Makovsky 2021 Syracuse University

Mesoproterozoic Basement From The Central And Southern Appalachians Reveal High-Temperature Magmatic Conditions And Non-Laurentian Origin Of Earth's Most Zircon Fertile Magmas, Kyle Makovsky

Dissertations - ALL

The Mesoproterozoic (1.4-0.9 Ga) Grenville Orogeny led to the formation of the supercontinent Rodinia. One unique characteristic of the Grenville Orogeny is that it produced a volumetrically significant amount of zirconium- (Zr) enriched granitoids, evidently more than any period both prior to and after the Grenville. To investigate this further, Mesoproterozoic basement rocks were sampled along the axis of the current Appalachian Mountains from western North Carolina north to southern New York, as well as from the northern Andes in southern Colombia. Zircon was extracted from these rocks to exploit its propensity to incorporate several isotopic tracers useful in determining …


Carbonate Paleothermometry In Fayetteville Green Lake, New York, Micah Wiesner 2021 Syracuse University

Carbonate Paleothermometry In Fayetteville Green Lake, New York, Micah Wiesner

Theses - ALL

Lacustrine carbonates are important paleoclimate archives, but unknowns in the seasonal timing and depth of precipitation obscure the interpretation of temperatures associated with them. The clumped isotope paleothermometer records the formation temperature T(D47) of carbonates. This study examines a set of lacustrine carbonates formed in the water column, in addition to carbonate from a sediment core, to better understand the depth and seasonality of carbonate formation in a lacustrine setting. We test that, regardless of season and formation temperature, lacustrine carbonates form in isotopic equilibrium with respect to D47 and d18O fractionation. Further, we account for the effect of our …


Mesoproterozoic Basement From The Central And Southern Appalachians Reveal High-Temperature Magmatic Conditions And Non-Laurentian Origin Of Earth’S Most Zircon Fertile Magmas, Kyle Makovsky 2021 Syracuse University

Mesoproterozoic Basement From The Central And Southern Appalachians Reveal High-Temperature Magmatic Conditions And Non-Laurentian Origin Of Earth’S Most Zircon Fertile Magmas, Kyle Makovsky

Dissertations - ALL

The Mesoproterozoic (1.4-0.9 Ga) Grenville Orogeny led to the formation of the supercontinent Rodinia. One unique characteristic of the Grenville Orogeny is that it produced a volumetrically significant amount of zirconium- (Zr) enriched granitoids, evidently more than any period both prior to and after the Grenville. To investigate this further, Mesoproterozoic basement rocks were sampled along the axis of the current Appalachian Mountains from western North Carolina north to southern New York, as well as from the northern Andes in southern Colombia. Zircon was extracted from these rocks to exploit its propensity to incorporate several isotopic tracers useful in determining …


Local- And Regional-Scale Forcing Of Glacier Mass Balance Changes In The Swiss Alps, Saeideh Gharehchahi, Thomas J. Ballinger, Jennifer L.R. Jensen, Anshuman Bhardwaj, Lydia Sam, Russell C. Weaver, David R. Butler 2021 Jacksonville State University

Local- And Regional-Scale Forcing Of Glacier Mass Balance Changes In The Swiss Alps, Saeideh Gharehchahi, Thomas J. Ballinger, Jennifer L.R. Jensen, Anshuman Bhardwaj, Lydia Sam, Russell C. Weaver, David R. Butler

Research, Publications & Creative Work

Glacier mass variations are climate indicators. Therefore, it is essential to examine both winter and summer mass balance variability over a long period of time to address climate-related ice mass fluctuations. In this study, we analyze glacier mass balance components and hypsometric characteristics with respect to their interactions with local meteorological variables and remote large-scale atmospheric and oceanic patterns. The results show that all selected glaciers have lost their equilibrium condition in recent decades, with persistent negative annual mass balance trends and decreasing accumulation area ratios (AARs), accompanied by increasing air temperatures of +0.45 C decade 1. The controlling factor …


Changes In Tropospheric Ozone Associated With Strong Earthquakes And Possible Mechanism, Feng Jing, Ramesh P. Singh 2021 China Earthquake Administration

Changes In Tropospheric Ozone Associated With Strong Earthquakes And Possible Mechanism, Feng Jing, Ramesh P. Singh

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The index of ozone anomaly (IOA) has been proposed to detect changes in tropospheric ozone associated with strong earthquakes. The tropospheric ozone prior and after the 2008 Wenchuan earthquake has been analyzed using IOA. Atmospheric infrared sounder ozone volume mixing ratio (O3 VMR) at different pressure levels (600, 500, 400, 300, 200 hPa) for an 18-year period 2003–2020 has been considered to identify the unique behavior associated with the strong earthquakes. Our results show distinct enhancement in tropospheric ozone occurred 5 d (7 May 2008) prior to the main event and distributed along the Longmenshan fault zone. An enhancement in …


Interaction Of Aqueous U(Vi) With Goethite, Montmorillonite, And Uo2(S), Anshuman Satpathy 2021 Washington University in St. Louis

Interaction Of Aqueous U(Vi) With Goethite, Montmorillonite, And Uo2(S), Anshuman Satpathy

McKelvey School of Engineering Graduate Student Theses & Dissertations

Uranium contamination in subsurface environments is a matter of great concern throughout the world. Fate and transport of uranium in the subsurface can be controlled by U(VI) adsorption and reduction onto common iron (oxy)hydroxides and clay minerals. Aqueous U(VI) can also exchange uranium atoms with solids comprised of uranium which can potentially lead to changes in the morphology of the uranium-containing solids and affect their stability. First, the performance of multiple surface complexation models (SCMs) on adsorption of U(VI) onto goethite was analyzed for a broad range of input conditions. Individual models could fit the data for which they were …


Molybdenite Re–Os, Titanite And Garnet U–Pb Dating Of The Magushan Skarn Cu–Mo Deposit, Xuancheng District, Middle–Lower Yangtze River Metallogenic Belt, Yue Li, Feng Yuan, Simon M. Jowitt, Fangyue Wang, Xiangling Li, Yufeng Deng, Yunyue Wang, Taofa Zhou 2021 Hefei University of Technology

Molybdenite Re–Os, Titanite And Garnet U–Pb Dating Of The Magushan Skarn Cu–Mo Deposit, Xuancheng District, Middle–Lower Yangtze River Metallogenic Belt, Yue Li, Feng Yuan, Simon M. Jowitt, Fangyue Wang, Xiangling Li, Yufeng Deng, Yunyue Wang, Taofa Zhou

Geoscience Faculty Research

© 2020 Elsevier B.V. The Magushan skarn Cu–Mo deposit is a representative example of the skarn mineralization occurring within the Xuancheng ore district of the Middle–Lower Yangtze River Metallogenic Belt of eastern China. The precise age of an ore deposit is important for understanding the timing of mineralization relative to other geological events in a region and to fully place the formation of a mineral deposit within the geological context of other processes that occur within the study area. Here, we present new molybdenite Re–Os and titanite and andradite garnet U–Pb ages for the Magushan deposit and use these data …


A Triple Oxygen Isotope Analysis Of Altered Oceanic Crust And Its Buffering Effect On The Steady State Oxygen Isotope Composition Of Seawater, Jesse P. McGunnigle 2021 University of New Mexico

A Triple Oxygen Isotope Analysis Of Altered Oceanic Crust And Its Buffering Effect On The Steady State Oxygen Isotope Composition Of Seawater, Jesse P. Mcgunnigle

Earth and Planetary Sciences ETDs

The secular chemical marine sediment trend showing an increase in δ18O over geologic time has traditionally been investigated using δ18O modelling of ancient ocean compositions, ocean surface temperatures, and sample diagenetic alteration. This study presents a triple oxygen isotope mass balance for the oceans using high precision δ18O and Δ'17O measurements of altered oceanic crust. The mass balance model predicts an ice-free seawater with δ18O = -0.29‰ and Δ’17O = -0.002‰ with steady state reached at approximately (0.5 to 1)×109 years. Modifications to the hydrothermal alteration and …


Effects Of The Triassic-Jurassic Central Atlantic Magmatic Event Recorded In Continental Strata In Western Pangea: The Δ13c Record Of Warner Valley & Zion National Park, Dennis Mmasa 2021 University of Arkansas, Fayetteville

Effects Of The Triassic-Jurassic Central Atlantic Magmatic Event Recorded In Continental Strata In Western Pangea: The Δ13c Record Of Warner Valley & Zion National Park, Dennis Mmasa

Graduate Theses and Dissertations

The Triassic is a period of abrupt climate change bracketed by mass extinctions including one driven by the eruption of the Central Atlantic Magmatic Province (CAMP) in the Late Triassic. The Moenave Formation (MF) of Utah and Arizona is ideal to investigate effects of the CAMP on continental strata distal to the eruptive center. This study focuses on the C-isotopic composition of bulk carbonate C from two localities, Blacks Canyon, Zion National Park, UT and Olsen Canyon within Warner Valley, UT. The data collected was used to document a chemostratigraphic record to compare to globally established records and bulk organic …


Dolomite Stoichiometry As A Proxy For Fluid Chemistry, Cameron J. Manche 2021 Western Michigan University

Dolomite Stoichiometry As A Proxy For Fluid Chemistry, Cameron J. Manche

Dissertations

The origin of massive dolomites is a contentious issue in geology. Because modern dolomite is rare, interpretation of ancient dolomites requires the use of proxy resources, most of which provide ambiguous information. High-temperature dolomite synthesis experiments have shown that dolomite stoichiometry, the degree of cation ordering, and reaction rate are controlled by Mg:Ca, temperature, molarity, and salinity of the formative solution. Thus, it is posited here that dolomite stoichiometry may be a useful proxy for fluid chemistry, as are stable isotope and trace element composition of ancient dolomites. High-frequency sample intervals (cm-scale) from the Cretaceous Upper Glen Rose Formation (Comanche …


Geological Problems With Microbiological Solutions: Deciphering The Authigenesis Of Calcite, Dolomite, And Native Sulfur In Salty Environments, Amanda L. Labrado 2021 University of Texas at El Paso

Geological Problems With Microbiological Solutions: Deciphering The Authigenesis Of Calcite, Dolomite, And Native Sulfur In Salty Environments, Amanda L. Labrado

Open Access Theses & Dissertations

Microbial activity is known to impact the formation and alteration of many different rock types. For carbonate caprock (CCR), a lithology found on salt diapirs, it is generally accepted that microbial activity drives the precipitation of carbonate minerals, forming limestone and/or dolomite and native (elemental) sulfur. It appears that there are two types of CCR: 1) limestone associated with native sulfur (S0) and 2) limestone associated with dolomite. The mechanics of CCR formation are poorly understood. For example, it is unclear why native sulfur and dolomite are rarely found in the same CCR assemblage, and why either are formed at …


Petrogenesis Of Hawaiian Lavas: Investigations Using Radiogenic And Non-Traditional Stable Isotopes, Christopher Defelice 2021 University of Nevada, Las Vegas

Petrogenesis Of Hawaiian Lavas: Investigations Using Radiogenic And Non-Traditional Stable Isotopes, Christopher Defelice

UNLV Theses, Dissertations, Professional Papers, and Capstones

Earth’s mantle is the most voluminous part of the planet and is inaccessible to direct investigations. It is only possible to study it through indirect methods, such as the chemical makeup of erupted lavas. The Hawaiian Islands are thought to be the product of the mantle plume hypothesis, sometimes called a hot spot. Material from the Earth’s mantle is brought to the surface and erupted as magnesium rich lavas and form basalts. Hawaii is the longest lived active hot spot on Earth and makes it an ideal candidate for understanding the evolution of the Earth’s mantle and how lavas cool …


Chronicling Magma Transit Beneath Hawaiian Volcanoes: Every Isotope A Word, Every Crystal A Story, Jonathan Pinko 2021 University of Nevada, Las Vegas

Chronicling Magma Transit Beneath Hawaiian Volcanoes: Every Isotope A Word, Every Crystal A Story, Jonathan Pinko

UNLV Theses, Dissertations, Professional Papers, and Capstones

At many oceanic volcanoes, such as Hawaii, mantle-derived magmas migrate to crustal level magma chambers, where they accumulate before eruption. Understanding the magma chamber residence times, or the time gaps between the arrivals of new magmas and eruptions, is important in volcanic hazard mitigation. Here I apply iron and magnesium isotope effects in olivines to constrain these times at Hawaiian volcanoes. Combined with published data, I present bulk ?56Fe (-1.706 to 0.489) and ?26Mg (-0.400 to 0.356) in 108 Hawaiian olivines erupted from the pre-shield, shield, and post-shield stages. The Hawaiian olivine ?56Fe and ?26Mg represent the largest Fe-Mg isotope …


Carbon-Isotope Chemostratigraphy And Fluvial Sedimentology Of The Moenave Formation, Utah, Jordan Oefinger 2021 University of Arkansas, Fayetteville

Carbon-Isotope Chemostratigraphy And Fluvial Sedimentology Of The Moenave Formation, Utah, Jordan Oefinger

Graduate Theses and Dissertations

The end Triassic extinction (ETE) is one of the largest mass extinction events of the Phanerozoic, and it has been hypothesized that this event, as well as the Triassic-Jurassic (TJ) boundary, are preserved within the Moenave Formation of the Colorado Plateau. Identification of this boundary within southwest Utah sections of the Colorado Plateau region is critical for better understanding the relationship between climate change and the ETE in terrestrial, low latitude paleoenvironments. The Moenave Formation is well exposed in Blacks Canyon of Zion National Park and in the nearby Warner Valley, where detailed sedimentologic observations and carbon isotope sampling have …


200— Chemical Analysis Of Slag From Standish, Ny, Maria Leonard, Dori Farthing 2021 SUNY Geneseo

200— Chemical Analysis Of Slag From Standish, Ny, Maria Leonard, Dori Farthing

GREAT Day Posters

From 1883 to 1907, magnetite was smelted in Standish, NY. During this time, a large amount of slag, a byproduct of smelting, was created. The slag is now in a pile that covers ~13 acres in the northeastern region of the Adirondacks. The slag at the site has been classified into 6 broad types based on their physical properties. Exemplars of select types were crushed and analyzed by X-ray fluorescence spectroscopy (XRF). Both major elements and trace element data was collected for these samples. The XRF results indicate that all Standish slag is dominated by SiO2, CaO, and Fe2O3(t) regardless …


369— Comparison Of Wilkins Creek And Spring Creek Stream Chemistries, Victoria Taylor, Brooke Stickles 2021 SUNY Geneseo

369— Comparison Of Wilkins Creek And Spring Creek Stream Chemistries, Victoria Taylor, Brooke Stickles

GREAT Day Posters

A stream's chemistry and health can be affected by seasonal fluctuations, environment and land usage. Wilkins Creek and Spring Creek are tributaries of Conesus Lake located in Livonia, New York. The two streams flow through varying terrain. Wilkins Creek flows predominantly through wetlands, residential and agricultural land. Spring Creek runs through the village of Livonia. The different environments may result in altered stream chemistries. An analysis of water chemistry was taken at different points in Wilkins Creek and Spring Creek before they converged. Alkalinity, chloride, oxygen, pH, conductivity, and water temperature were measured at each location. Samples were collected and …


Diversity – Independent Factors Predict Elevated Extinction Rates, Dustin Perriguey, Corinne Myers, Jason Moore, Louis Scuderi 2021 University of New Mexico

Diversity – Independent Factors Predict Elevated Extinction Rates, Dustin Perriguey, Corinne Myers, Jason Moore, Louis Scuderi

Earth and Planetary Sciences ETDs

Multiple linear regression was used to determine the relationships between diversity-independent factors (i.e., abiotic, climatic) 2, 5, and 10 Myrs-prior to the most elevated Phanerozoic extinctions. We constructed five abiotic variables from Phanerozoic proxy records1–5 to compare to extinction rates: mean temperature, temperature instability, carbon cycle instability, continental weathering rates, and habitat instability. All three models were statistically significant (P < 0.05) and explained > 70% of the variation in Alroy’s6 three-timer generic extinction rates. However, the 2 Myr-prior model explained the most variance in extinction rates and had the most predictive power, based on adjusted and predictive R2 (~ 72% and 41%, respectively). Carbon …


Diversity – Independent Factors Predict Elevated Extinction Rates, Dustin Perriguey 2021 University of New Mexico

Diversity – Independent Factors Predict Elevated Extinction Rates, Dustin Perriguey

Earth and Planetary Sciences Faculty and Staff Publications

Multiple linear regression was used to determine the relationships between diversity-independent factors (i.e., abiotic, climatic) 2, 5, and 10 Myrs-prior to the most elevated Phanerozoic extinctions. We constructed five abiotic variables from Phanerozoic proxy records1–5 to compare to extinction rates: mean temperature, temperature instability, carbon cycle instability, continental weathering rates, and habitat instability. All three models were statistically significant (P < 0.05) and explained > 70% of the variation in Alroy’s6 three-timer generic extinction rates. However, the 2 Myr-prior model explained the most variance in extinction rates and had the most predictive power, based on adjusted and predictive R2 (~ 72% and 41%, respectively). Carbon …


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