Geochemistry Commons^™

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 …

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 …

Geochemical Processes And Controls Affecting Water Quality Of The Karst Area Of Big Creek Near Mt. Judea, Arkansas, V. Brahana, J. Nix, C. Kuyper, T. Turk, F. Usrey, S. Hodges, C. Bitting, K. Ficco, E. Pollock, R. Quick, B. Thompson, J. Murdoch

Journal of the Arkansas Academy of Science

Karst regions typically are considered to be vulnerable with respect to various land-use activities, owing to the intimate association of surface and groundwater and lack of contaminant attenuation provided by most karst aquifers. Inasmuch as the soluble rocks of the karst landscape can be dissolved to create large, rapid-flow zones that compete successfully with surface streams, groundwater and subsurface flow represent a much larger component of the hydrologic budget in karst regions than in areas where non-soluble rocks predominate. Karst areas typically are distinguished by being unique, but some general approaches can be applied to characterize the hydrology of the …

Metal Mobilization In Groundwater, Bauxite, Ar, Steven Alexander Hamlin

Graduate Theses and Dissertations

The Wilcox Aquifer of Bauxite, AR contains bauxite ore deposits that may contribute heavy metals to groundwater. Twenty-four wells were sampled for aluminum, iron, manganese, zinc, lead, barium, nitrate, sulfate, sodium, alkalinity, calcium, magnesium, chloride, pH, total organic carbon, and total dissolved solids. A Wilcoxon Rank-Sum compared the similarity of the three geographic areas covered in the study. All parameters for wells in Bauxite and Sardis failed to reject the null hypothesis, signifying that wells all occupy the Saline Formation. 2/3rds of the parameters from BFI261 and the Bauxite region did not agree, suggesting the two areas do not occupy …

Solubility And Detectability Of Hydrocarbons On The Surface Of Titan, Sandeep Singh

Graduate Theses and Dissertations

Titan’s thick atmosphere is enriched with organic compounds and its surface holds reservoirs of hydrocarbons. This makes Titan the only other candidate in our solar system (apart from Earth) to have stable liquid at the surface. The stability and characteristics of liquid and ices on the surface of Titan are of high importance in understanding its surface-atmosphere interactions. Titan’s hydrological cycle is similar to what we see on Earth, with the exception of methane (CH4) and ethane (C2H6) taking the place of water. The smoggy atmosphere veils the surface of Titan from the view of Cassini spacecraft, except at seven …

Stable Isotopes As A Tool To Characterize Carbon Cycling And Develop Hydrologic Budgets In Mantled Karst Settings, Katherine Knierim

Graduate Theses and Dissertations

Isotopes of water (δ2H/δ18O), carbon dioxide (δ13C-CO2), and dissolved inorganic carbon (δ13C-DIC) were used to explore water quality, trace carbon cycling, and quantify recharge sources through mantled karst and into Blowing Spring Cave (BSC). Of the possible sources of contamination in the BSC recharge area, septic-tank effluent was hypothesized to degrade water quality at the spring outlet of BSC because of the dominance of septic tanks for waste treatment, unsuitable topography and soil for septic-tank absorption fields, increased nitrate and chloride concentrations concomitant with increased urbanization, and increased Escherichia coli with discharge. Carbon cycling between the soil and BSC was …

Source Constraints Of Ore Metals In Mississippi Valley-Type Deposits In Central And Eastern Tennessee Using Pb Isotopes, Austin Moyers

Graduate Theses and Dissertations

The Mississippi Valley-Type (MVT) Central and East Tennessee (TN) Districts contain economically significant lead-zinc deposits that occur in the Early Ordovician carbonates of the Knox Group. Although both districts share similar host rock, have similar temperatures of formation, and typically fill open spaces of collapse breccias or replace their host carbonates, previous studies may suggest that these ores did not form from the same mineralizing fluids and may have different Pb sources. Nu Plasma MC-ICP-MS Pb isotopic analyses on sulfides from Central and East TN were conducted and the metal sources evaluated. Results were plotted on covariation diagrams with respect …

Terrestrial Impacts Of The Central Atlantic Magmatic Province On Western Pangea, Todd Kenneth Knobbe

Graduate Theses and Dissertations

Earth's climate is predominantly controlled by the fluctuation of greenhouse gases, specifically CO2 and CH4, over geologic time. The late Triassic is a period of abrupt climate change that has been associated with a disruption to the global carbon cycle due the emplacement of the Central Atlantic Magmatic Province (CAMP). Evidence has shown that this global carbon cycle perturbation may be the culprit for the end-Triassic extinction. The Whitmore Point Member of the Moenave Formation is a lacustrine deposit with a disputed age of either late Triassic or early Jurassic and currently no absolute dating techniques can be applied to …

Hydrogeology And Chemical Characterization Of Hydrocarbon In Domestic Water Wells, Rancho Villa Subdivision, Rogers, Arkansas, Janelle Renee Sherman

Graduate Theses and Dissertations

This project is centered on the Rancho Villa community in Rogers, Arkansas where several residents have had hydrocarbon contamination in their domestic water wells. The goal of this project was to understand the hydrogeology in the study area, characterize the contaminant chemically, and determine the source of the contaminant. The hydrogeology of the area was determined from previous theses. Seventeen samples were taken from the wells in the Rancho Villa community; each sample was analyzed for geochemical parameters and by Gas Chromatography/Mass Spectrometry (GC/MS) for organic compounds analysis. Four of the 17 samples had a visible non-aqueous layer of hydrocarbon …

Assessment And Conceptualization Of Groundwater Flow In The Edwards Aquifer Through The Knippa Gap In Uvalde County, Texas, Jennifer Raye Adkins

Graduate Theses and Dissertations

The Edwards aquifer is one of the major regional karst aquifers in the United States, with an average withdrawal of 950 million liters per day (L/d). This investigation focuses on the connection between the Uvalde pool and the San Antonio pool of the Edwards aquifer, known as the Knippa Gap, west of the San Antonio metropolitan area in Uvalde County. This is a major zone of recharge to the Edwards aquifer and is approximately 6.4 km wide. The Knippa Gap is bounded by northeast trending faults of the Balcones Fault Zone (BFZ) on the north (specifically the Cooks and Trio …

Magnesium Isotopic Compositions Of The Moon And Achondrites: Implications For Their Origin And Evolution, Fatemeh Sedaghatpour

Graduate Theses and Dissertations

The main objectives of this thesis are to estimate Mg isotopic compositions of the Moon and achondrites, to understand the behavior of Mg isotopes during magmatic differentiation processes in different planetary bodies, and to evaluate the extent of Mg isotopic heterogeneity in the solar system. In order to achieve these goals, Mg isotopes have been measured for 47 well-characterized lunar samples and 22 differentiated meteorites by MC-ICPMS. The limited Mg isotopic variations among mare and highland regolith, mare breccias, and highland impact-melt rocks reflect negligible Mg isotope fractionation during lunar surface processes (e.g. solar wind, cosmic rays, micrometeorite bombardments, meteorite …

Assessing Ageing At Beaver Reservoir, Northwest Arkansas: Limnological, Geochemical & Paleolimnological Approach, Byron Anthony Winston

Graduate Theses and Dissertations

Access to potable water has been arguably one of the most important requisites for the advancement of human civilization on earth. As a result, man in his infinite wisdom devised the dam and formed reservoirs, (man- made lakes), to exploit water resources at will. In all natural lakes and reservoirs changes occur in the water quality parameters as it relates to chemical nutrients, temperature and turbidity over time. These changes are collectively referred to as "Reservoir Ageing", of which sedimentation and eutrophication are primary. Reservoir Ageing has consequences which adversely affect and defeat many of the intended uses of the …

An Analysis Of The Stability And Transport Of Co2 On Mars And Iapetus: Increasing Accuracy Via Experiments And Photometry, David Garrison Blackburn

Graduate Theses and Dissertations

Volatile transport of carbon dioxide is most relevant on two planetary bodies in our solar system: Mars and Iapetus. We experimentally measured the sublimation rate of CO2 ice under simulated martian conditions and developed a model based on our experimental results. We experimentally verified that solar irradiance is the primary control for the sublimation of CO2 ice on the martian poles with the amount of radiation striking the surface being controlled by variations in the optical depth, ensuring the formation and sublimation of the seasonal cap. Our model, supported by comparison of MGS-MOC and MRO-HiRISE images, shows that ~ 0.4 …

Linkage Of Asteroids And Meteorites By The Study Of Terrestrial Analogs, Daniel Robert Ostrowski

Graduate Theses and Dissertations

Asteroids are one group of the bodies that can provide insights into the origin and early history of the solar system. Asteroids are considered to be fairly pristine, with alterations only occurring to their surface from the space environment. Studying them provides opportunities to learn about the primordial solar system, its materials, and processes and how it evolved into the current condition. Many asteroids have been discovered, but few have their surface compositions determined. The C and X complexes provide a difficulty in determination because their near infrared spectrum is featureless.

The C asteroids have been long associated with the …

New Infrared Spectral Data For 27 Asteroids: An Investigation Of Meteorite-Asteroid Relationships By Using The Modified Gaussian Model, Katherine Marie Gietzen

Graduate Theses and Dissertations

Asteroids provide unique insights into the origin and early history of the solar system. Since asteroids are considered to be fairly pristine, studying them provides opportunities to learn more about the primordial solar system, its materials, processes and history. Since the discovery in 1801 of the first asteroid, Ceres, during the era when everyone was searching for the "missing planet", astronomers have been trying to understand what they are, where they came from, why they exist and what they can tell us about how our solar system formed and evolved.

Within the asteroid population are a number of sub-populations, the …

Chemistry Of The Spring Waters Of The Ouachita Mountains Excluding Hot Springs, Arkansas, George H. Wagner, Kenneth F. Steele

Arkansas Water Resources Center Technical Reports

This report is based on the chemical analysis of the waters from 93 springs and 9 wells. Springs, when free from metal plumbing, provide an uncontaminated source of the ground water and it was desired to obtain water uncontaminated with metals. A few wells were added to the list, usually because of their unique location in the sampling grid.

Geochemistry Of A Carbonatite In Montgomery County, Arkansas, George H. Wagner, Ronald H. Konig, Michael D. Jones

Journal of the Arkansas Academy of Science

No abstract provided.