Geochemistry Commons^™

Testing Of The Late-Ordovician Pre-Gice Warm Water Carbonate Hypothesis In Alabama, Brandon Euker, Stacey Law

Senior Honors Projects, 2010-2019

The Guttenberg Carbon Isotope Excursion (GICE) (uppermost Sandbian-lower Katian, Late Ordovician) has been suggested to represent the transition from a Cambrian-Ordovician greenhouse world to Late Ordovician icehouse world. This transition is thought to coincide with a proposed shift from deposition of warm water carbonate rocks to cool water carbonate rocks in the North American midcontinent. We used oxygen isotopes (d¹⁸O) of conodonts to test the idea that the rocks below the GICE interval represent a consistently warm environment. Conodonts were isolated from samples of the Chickamauga Group collected at the Tidwell Hollow section in Blount County, AL, from …

Characterizing The Earliest Stages Of Partial Melting: A Study Of The Pyrometamorphic Aureole Of Miocene Mt. Perkins Pluton, Northwest Arizona, Mathew Beshears

UNLV Theses, Dissertations, Professional Papers, and Capstones

Partial melting is an important process in the evolution of continental crust. Due to its progressive nature, evidence of the early stages of partial melting is often overprinted by later, advanced stages of partial melting. Experimental work has provided a model for the early stages of partial melting, but is limited to timescales of hours to weeks. Pyrometamorphic environments within the contact aureole of mafic intrusions provide natural laboratories for the study of the earliest stages of partial melt production on geologic time scales of 102 collected along two traverses of the tilted pyrometamorphic aureole of the Mt. Perkins pluton …

Investigating Mineral Stability Under Venus Conditions: A Focus On The Venus Radar Anomalies, Erika Kohler

Graduate Theses and Dissertations

Radar studies of the surface of Venus have identified regions with high radar reflectivity concentrated in the Venusian highlands: between 2.5 and 4.75 km above a planetary radius of 6051 km, though it varies with latitude. Previous research has proposed several theories on the source of these anomalies, including increased surface roughness, metallic materials with higher dielectric constants, or ferroelectric materials. Prior work suggests several processes that could be the origin of these anomalies, such as surface-atmospheric interactions or low lying clouds or fog. Alternatively, these anomalies could result from a semi-metallic compound trapped at the cooler conditions in the …

Isotopic Identification Of Multiple Contributors Of Metal Ions In Mississippi Valley-Type Ore Deposits Along The Cincinnati Arch In South-Central Kentucky, William Travis Garmon

Graduate Theses and Dissertations

Mississippi Valley-Type (MVT) ores are economically-viable deposits of sulfide minerals, often dominated by sphalerite (zinc-sulfide) in carbonate facies, and galena (lead-sulfide) in siliciclastic facies. MVT ores precipitate from migrating fluids, which carry base metals often complexed with chlorine ions within a basinal brine. This study identifies metal-contributing source-regions of the Burkesville MVT deposit using Pb-isotope ratios within sphalerite samples collected from the Burkesville deposit. The deposit is found in south-central Kentucky within the Middle-Tennessee ore district along the crest of the Cincinnati Arch, which is the anticlinal divide between the Appalachian Basin and the Illinois Basin. Competing theories argue that …

A Geochemical Analysis Of The Arkansas Novaculite And Comparison To The Siliceous Deposits Of The Boone Formation, John Byron Scott Philbrick

Graduate Theses and Dissertations

Geochemical analyses of the Arkansas Novaculite, located within core structures of the Ouachita Mountains in west-central Arkansas, and penecontemporaneous chert of the lower Boone Formation, located atop the Springfield Plateau of southwest Missouri, northwest Arkansas, and northeast Oklahoma, have identified a significant concentration of both aluminum and potassium. This would seem to eliminate a biogenic origin and favor a volcanic source of the silica that comprises these units. Trace and rare earth element (REE) analysis also suggests that the Arkansas Novaculite and the chert in the lower Boone Formation may have both been formed from the same volcanic source.

The …

Resolving Paragneiss Provenance At Grollier Lake In The Athabasca Granulite Terrane, Western Canadian Shield, Dustin Ply

Graduate Theses and Dissertations

U-Pb crystallization ages of metamorphic and detrital zircons from all three paragneiss samples fall into the range of ca. 1.85-2.59 Ga, excluding two much older grains. Evidence suggests that the paragneiss of Grollier Lake record deformation exclusively from the Taltson and Trans-Hudson orogenies. It is apparent from geochronological data that the Taltson orogeny played an exceedingly larger role in the deformation of these rocks than the Trans-Hudson. Deposition of the paragneiss protoliths most likely culminated between ca. 2037-1994 Ma with metamorphism ceasing by 1852.1 ± 11.1 Ma. The oldest overgrowth considered to be concordant is 1994 ± 12 Ma and …

Understanding The Surface Induced Phosphorylation Of Prebiotic Molecules By Schreibersite, Danna Qasim

Master of Science in Chemical Sciences Theses

The study of the surface of a meteoritic mineral, schreibersite (Fe,Ni)₃P, was investigated to provide insight into the role of the mineral’s surface in aqueous-phase phosphorylation reactions. The optimization of a custom-designed ultrahigh vacuum (UHV) apparatus and Fe₂NiP (schreibersite) surface was performed to permit surface science analysis. The bare surface was characterized by scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS), which showed some oxidation and segregation of phosphorous within the near-surface region. The interaction and/or reaction of water (H₂O), methanol (CH₃OH), formic acid …

Evaluation Of Groundwater Quality In Paleozoic Aquifers Using Gis Techniques, Central Texas, Garrett R. Harris

Electronic Theses and Dissertations

Lab analyses of groundwater chemistry from monitoring wells completed in the Paleozoic Aquifers surrounding the Llano Uplift of Central Texas has been recorded and made available to the public through the Texas Water Development Board (TWDB). This study evaluated the results of these data dating back to the 1940s to determine changes over time, the dynamics of the hydrologic system, and the locations where hydraulic connectivity is most probable. The initial results established two distinct hydrologic systems that required the separation of the northern from the southern region. The northern sub-region (NSR) contains the largest expanse of continuity of both …

Apatite Helium Thermochronology Of The Blue Nile Canyon, Ethiopian Plateau, Nathaniel C. Blackburn

Masters Theses & Specialist Projects

The Ethiopian Plateau, situated in the northernmost part of the East African Rift System, has been uplifted and incised by the Blue Nile River, creating the 1.5 km-deep Blue Nile Canyon, the only extensive canyon within the Nile drainage basin. Much of this canyon incision is related to the Ethiopian Plateau uplift, which is due to a combined tectonic influence linked to the East African Rift System and the Afar Mantle Plumerelated upwelling since the Oligocene. The Blue Nile Canyon incision followed this plume-related upwelling, which resulted in extensive flood basalt emplacement around ~30 Ma. This study employs low-temperature apatite …

Mineralogy And Environmental Geochemistry Of Slag In Lower Area One, Butte, Montana, Jenna Kaplan

Graduate Theses & Non-Theses

Butte, Montana is the host to a Cu-Mo porphyry deposit and has been a location of mining interest since 1864. Once copper ore is removed from this deposit it goes through a smelting process. Copper smelting processes consist of roasting, smelting, concentrating, and fire refining. During smelting, metals are separated from the waste, or gangue material. Slag is the waste material from these processes. Non-ferrous slag, such as a copper ore, removes iron and silica from the original ore. There is much interest in slag postproduction for there is often still a significant weight percent of metals trapped within a …

Anaerobic Dissociation Of Thiocyanate Under Controlled Ph And Temperature, Alero Gure

Graduate Theses & Non-Theses

Thiocyanate (SCN-) is formed from both natural and industrial processes, including the use of cyanide to process gold and silver ores rich in sulfide minerals. In mining operations however, thiocyanate also plays a role as an alternative lixiviant to cyanide for leaching gold and silver out of their ores. Thiocyanate may be less toxic than cyanide but it is more stable and has proven to be more difficult to destroy in mining effluents. In addition, just like cyanide, an environmental contaminant of concern – nitrate – is the final product of the oxidation of thiocyanate.

This study investigated the chemical …

Using Naturally Occurring Radon 222 As A Tracer To Quantify Groundwater Fluxes To Streams, Mandy Machinal

Graduate Theses & Non-Theses

Naturally occurring radon in groundwater was used to test radon mixing models. Two different mixing models were used to quantify groundwater fluxes to streams; an analytical solution and a finite difference method. Two different bodies of waters were used in this study. The first location was Johnson Creek located in Grant-Kohrs Ranch in Deer Lodge, Montana. This is a small creek where lots of sampling points were taken. The stretch of Johnson Creek where radon samples were collected was about 0.34 km long with a flowrate between 0.01 m3/s and 0.017 m3/s. The second location was Merced River located in …

Low-Temperature Artificial Maturation Studies Of Type Ii And Type Iii Kerogens: Implications For Biogenic Gas Production, Albert Willy Nguena Kamga

Chemistry & Biochemistry Theses & Dissertations

Ancient organic matter (OM) in shales and coals, known mainly as Type II and Type III OM are known to produce both biogenic, thermogenic gas and oil. In this dissertation, mild artificial maturation, via closed system pyrolysis, is employed to determine the thermal reactivity of Type II and Type III OM beyond diagenesis. We select three Type II kerogens: i) Type II kerogen isolated from recent cores (3.3 Ma, Ro = 0.28) recovered from an upwelling basin in Namibia, Africa referred to as ODP Sediment, ii) Type II-S isolated from sediments (150 Ma, Ro = 0.38) recovered from an outcrop …

Geochemical And Petrological Studies On The Origin Of Nickel-Copper Sulfide Mineralization At The Eagle Lntrusion In Marquette County, Michigan, Benjamin Davis Hinks

Masters Theses

The Eagle magmatic intrusion is located in the Upper Peninsula of Michigan in Marquette County. It hosts a high grade magmatic nickel-copper sulfide ore deposit. Country rocks surrounding the Eagle intrusion are metamorphosed slate and greywacke of the Proterozoic Michigamme Formation and Archean granite-gneiss. The aim of this thesis is to characterize the magmatic sulfide mineral deposit at Eagle and to establish its relationship to the surrounding host rocks of the Baraga Basin area.

The Eagle East intrusion is located 600 meters east of the Eagle intrusion. These two intrusions are similar in composition and sulfide mineralization. Sulfide textural domains …

Geochemical And Petrological Characterizations Of Peridotite And Related Rocks In Marquette County, Michigan, Andrew Lloyd Sasso

Masters Theses

This study characterizes the following rock units in Marquette County, Michigan in terms of geochemistry and petrology: (1) Presque Isle Peridotite, (2) Deer Lake Peridotite, (3) Yellowdog Peridotite, and (4) Black Rock Point Gabbro. Analyses were conducted to determine if any petrological or geochemical relationships exist between these units, and to assess the potential of these units to host magmatic sulfide deposits.

The generated data and chosen geotectonic proxies indicate that Black Rock Point Gabbro and Deer Lake Peridotite crystallized from unrelated magmas, probably during the formation of the Great Lakes Tectonic Zone (2.7-1.85 Ga). No evidence was found which …

Natural Acid Rock Drainage And Ferricrete Deposit Chemistry Of The Judith Mountains, Montana, Sara Edinberg

Graduate Theses & Non-Theses

The Judith Mountains are a low-elevation “island” mountain range in east-central Montana composed of a series of laccoliths and stocks cut by coarse-grained alkali granite and tinguaite dikes. The geology of the Judith Mountains in the vicinity of Red Mountain and Judith Peak, two of the tallest mountains in the range, is conducive to the creation of headwater streams that are naturally acidic. Extensive limonite staining on Red Mountain attests to the widespread presence of disseminated pyrite in hydrothermally altered porphyry rock. However, no major historical mining operations are known to the area. The acidic streams undergo neutralization in pH …

U-Pb Dating Of Speleogenetic Dolomite: A New Sulfuric Acid Speleogenesis Chronometer, Victor J. Polyak, Paula P. Provencio, Yemane Asmerom

International Journal of Speleology

The 1100-meter Big Room elevation level of Carlsbad Cavern, New Mexico USA, formed 4 Ma by hypogenic sulfuric acid speleogenesis (SAS). The age of the Big Room level of 4.0 ± 0.2 Ma was previously determined by dating alunite, a byproduct of speleogenesis, using the ⁴⁰Ar/³⁹Ar method. Duplication of these results is possible by radiometric dating of other byproducts interpreted to be speleogenetic (a byproduct of speleogenesis) such as calcite and dolomite in certain settings. XRD and TEM analyses of sample 94044, a piece of crust collected within the Big Room level of SAS just below Left …

Agriculture Causes Nitrate Fertilization Of Remote Alpine Lakes, Elizabeth J. Hundey, Sam S.D. Russell, Fred Longstaffe, Katrina A. Moser

Earth Sciences Publications

Humans have altered Earth’s nitrogen cycle so dramatically that reactive nitrogen (Nr) has doubled. This has increased Nr in aquatic ecosystems, which can lead to reduced water quality and ecosystem health. Apportioning sources of Nr to specific ecosystems, however, continues to be challenging, despite this knowledge being critical for mitigation and protection of water resources. Here we use D¹⁷O, d¹⁸O and d¹⁵N from Uinta Mountain (Utah, USA) snow, inflow and lake nitrate in combination with a Bayesian-based stable isotope mixing model, to show that at least 70% of nitrates in aquatic systems are anthropogenic …

Climate, Ecology, And Human Evolution During The Plio-Pleistocene, Scott Adam Blumenthal

Dissertations, Theses, and Capstone Projects

A major goal of paleoanthropology is to identify the selective pressures associated with hominin biological and behavioral evolution, yet establishing cause-effect relationships between climate, ecology, and human evolution remains problematic. This dissertation seeks to investigate hominin paleoecology in eastern Africa by reconstructing aspects of climate and ecology using stable isotope analysis.

The first part of this dissertation is focused on the ecology of primates and hominins. Modern tropical African ecosystems provide a useful model for understanding the ecological correlates of isotopic variation in the fossil record, and living primates provide a useful model for understanding the ecological significance of isotopic …

Processes Controlling Carbon Cycling In Antarctic Glacier Surface Ecosystems, Elizabeth A. Bagshaw, Martyn Tranter, Jemma L. Wadham, Andrew G. Fountain, A. Dubnick, S. Fitzsimons

Geology Faculty Publications and Presentations

Glacier surface ecosystems, including cryoconite holes and cryolakes, are significant contributors to regional carbon cycles. Incubation experiments to determine the net production (NEP) of organic matter in cryoconite typically have durations of 6-24 hours, and produce a wide range of results, many of which indicate that the system is net heterotrophic. We employ longer term incubations to examine the temporal variation of NEP in cryoconite from the McMurdo Dry Valleys, Antarctica to examine the effect of sediment disturbance on system production, and to understand processes controlling production over the lifetimes of glacier surface ecosystems. The shorter-term incubations have durations of …

Source Apportionment Of Atmospheric Particulate Matter In Developing Countries Using Trace Elements And Stable Metal Isotope Ratios, Nitika Dewan

Electronic Theses and Dissertations

The work presented herein details the source apportionment of atmospheric particulate matter in developing countries (Kyrgyzstan in Central Asia, metropolitan cities in Northern India, and Shenzhen in China) using trace elements and stable metal isotope ratios. The first study focused on the development of a novel method for the concomitant separation of rare-earth elements in environmental samples of any geological origin. The separation procedure is based on three extraction chromatographic materials, referred to as Sr.Spec, TRU.Spec, and Ln.Spec. This triple column arrangement enables the simultaneous isolation of pure Sr and Nd fractions in less than one day and with great …

Diffuse Co2 Degassing And The Origin Of Volcanic Gas Variability From Rincón De La Vieja, Miravalles And Tenorio Volcanoes, Guanacaste Province, Costa Rica, Aurelia Liegler

Dissertations, Master's Theses and Master's Reports

Volcanic gas emissions are an important key component for monitoring volcanic activity and magmatic input of carbon dioxide into the atmosphere as well as the assessment of geothermal potential in volcanic regions. Diffuse soil degassing of CO₂ at Rincón de la Vieja and Miravalles volcanoes, assessed with the commonly accepted accumulation chamber method, showed the concentration of gas emissions in evident hydrothermal surface features in secondary gas emission zones of the volcanoes. Analyses of fumarolic gases were conducted to investigate similarities and differences between the volcanoes and the possibility of continued magma injection into their source(s). An output of …

Taxonomy, Location Of Origin, And Health Status Of Proboscideans From Western Canada Investigated Using Stable Isotope Analysis, Jessica Z. Metcalfe, Fred Longstaffe, Christopher N. Jass, Grant D. Zazula, Grant Keddie

Earth Sciences Publications

We investigated the application of stable isotope analysis of proboscidean remains (collagen in bone/dentin/cementum and structural carbonate in enamel bioapatite) for genus-level identification of isolated specimens, assessment of geographic origins, and testing for nutritional stress. Mammoths (Mammuthus sp.) tended to have higher δ¹⁵N_col and lower δ¹³C_col than mastodons (Mammut americanum), but differences were not significant in every location. Determining the genus of isolated specimens may be possible for locations and time periods with good isotopic baselines, but environmental changes can confound interpretations. For example, an Alberta proboscidean with a δ¹⁵N …

Formation Of The Neoarchean Bad Vermillion Lake Anorthosite Complex And Spatially Associated Granitic Rocks At A Convergent Plate Margin, Superior Province, Western Ontario, Canada, Shuda Zhou, Ali Polat, Fred Longstaffe, Kunguang Yang, Brian J. Fryer, Crhis Weisener

Earth Sciences Publications

The Bad Vermilion Lake Anorthosite Complex (henceforth, the BVLA Complex) in western Ontario is one of the well-exposed, anorthosite-bearing, Archean layered intrusions in the Superior Province, Canada. This study presents new whole-rock major and trace element data for the various units of the Complex, oxygen isotope data for the anorthosite, and major and trace element data for the spatially associated granitic rocks intruding the BVLA Complex to constrain their petrogenetic and geodynamic origin. Zircons from granitic rocks have yielded a ²⁰⁷Pb/²⁰⁶Pb age of 2716 ± 18 Ma, constraining the minimum intrusion age of the Complex. Despite deformation …

Precipitation And Growth Of Barite Within Hydrothermal Vent Deposits From The Endeavour Segment, Juan De Fuca Ridge, John William Jamieson, Mark D. Hannington, Margaret K. Tivey, Thor Hansteen, Nicole M.-B. Williamson, Margaret Stewart, Jan Fietzke, David Butterfield, Matthias Frische, Leigh Allen, Brian Cousens, Julia Langer

United States Department of Commerce: Staff Publications

Hydrothermal vent deposits form on the seafloor as a result of cooling and mixing of hot hydrothermal fluids with cold seawater. Amongst the major sulfide and sulfate minerals that are preserved at vent sites, barite (BaSO₄) is unique because it requires the direct mixing of Ba-rich hydrothermal fluid with sulfate-rich seawater in order for precipitation to occur. Because of its extremely low solubility, barite crystals preserve geochemical fingerprints associated with conditions of formation. Here, we present data from petrographic and geochemical analyses of hydrothermal barite from the Endeavour Segment of the Juan de Fuca Ridge, northeast Pacific Ocean, …

Middle Preclassic Period Maya Greenstone "Triangulates": Forms, Contexts, And Geology Of A Unique Mesoamerican Groundstone Artifact Type, Terry G. Powis, Sherman Horn Iii, Gyles Iannone, Paul F. Healy, James F. Garber, Jaime J. Awe, Sheldon Skaggs, Linda A. Howie

Publications and Research

Over the past twenty years our understanding of the Middle Preclassic (900–300 BCE) period has become much clearer through archaeological investigations at a number of sites located in the Upper Belize River Valley region of the eastern Maya Lowlands. While the picture of Middle Preclassic Maya life, including their material culture, has sharpened, there are aspects that remain uninvestigated. One artifact type, identified as greenstone triangulates, has been found at several Belize Valley sites and in a variety of contexts. Although a number of these multifaceted, polished groundstone items have been recovered, little research has focused on their distribution and …

Comparison Of The Elemental Geochemistry Of The Arkansas Novaculite And The Boone Chert In Their Type Regions, Arkansas, J. Philbrick, E. Pollock, A. Potra

Journal of the Arkansas Academy of Science

The name Arkansas Novaculite was proposed by A.H. Purdue, 1909 to replace the name Arkansas Stone assigned by L. S. Griswold, 1892, but deemed too generic, to an interval of Early Devonian-Early Mississippian, very fine-grained, even textured, siliceous sedimentary rock famous for use as whetstones. The interval is exposed along the margins of the Benton Uplift, south flank of the Ouachita Mountains, west-central Arkansas, where it reaches a maximum thickness of 243.8 m (800 ft). The Arkansas Novaculite comprises informal lower and upper members characterized by massive beds of nearly pure novaculite, separated by a shale-bearing middle member that spans …

Dynamics Of Plume-Triple Junction Interaction: Results From A Series Of Three-Dimensional Numerical Models And Implications For The Formation Of Oceanic Plateaus, Mladen Dordevic, Jennifer Georgen

OES Faculty Publications

Mantle plumes rising in the vicinity of mid-ocean ridges often generate anomalies in melt production and seafloor depth. This study investigates the dynamical interactions between a mantle plume and a ridge-ridge-ridge triple junction, using a parameter space approach and a suite of steady state, three-dimensional finite element numerical models. The top domain boundary is composed of three diverging plates, with each assigned half-spreading rates with respect to a fixed triple junction point. The bottom boundary is kept at a constant temperature of 1350°C except where a two-dimensional, Gaussian-shaped thermal anomaly simulating a plume is imposed. Models vary plume diameter, plume …

Documenting Mantle And Crustal Contributions To Flood Basalt Magmatism Via Computational Modeling Of The Steens Basalt, Southeast Oregon, Sylvana J. Bendaña

All Master's Theses

Flood basalts are enormous volcanic events with volumes of volcanic cover and intrusive equivalents that are affected by and significantly affect the crust. Steens Basalt represents 31,800 km³ of flood basalt lavas that erupted in eastern Oregon ~16.8 Ma in less than 300,000 years. Analytical data of flows from a 1 km vertical exposure at Steens Mtn. documents time-transgressive changes in composition of two geochemically distinct units: (1) lower Steens, MgO-rich lavas with lower incompatible trace element concentrations and ⁸⁷Sr/⁸⁶Sr, and (2) upper Steens, MgO-poor, with higher incompatible trace element concentrations and ⁸⁷Sr/⁸⁶Sr. …

Sea Lamprey Mating Pheromone Registered By U.S. Environmental Protection Agency As First Vertebrate Pheromone Biopesticide, Marc Gaden, Marisa Lubeck

United States Geological Survey: Publications

Ann Arbor, MI – The U.S. Environmental Protection Agency registered a sea lamprey mating pheromone, 3kPZS, as the first ever vertebrate pheromone biopesticide in late December, 2015. Like an alluring perfume, the mating pheromone is a scent released by male sea lampreys to lure females onto nesting sites. Research and development of the mating pheromone was funded by the Great Lakes Fishery Commission, with additional support from the Great Lakes Restoration Initiative, in collaboration with federal government, university, and private industry partners.