Master of Science (MS), Bowling Green State University, 2019, Geology

Previous studies of the Upper Ordovician Trenton Limestone in northwestern Ohio interpreted an extensive subtidal carbonate platform on the northwest margin of Taconic foreland basin. This study focused on the subsurface facies analysis and paragenesis of the Trenton Limestone using eight different wells (3564, 20347, 2878, 2971, 2972, 2973, 3374, and 20239) in Hancock, Wood, and Wyandot counties. The wells were correlated using gamma-ray and density logs. Paragenesis was studied using petrography, SEM, EDAX, and cathodoluminescence. A total of 51 thin sections were used to study petrography, microfacies and diagenesis. Drill cores from two well sections (Core#3564 and Core# 3374) were used for lithofacies analysis. Cores 2878, 2971, and 2972 were used only for thin section analysis. The Trenton Limestone mainly consists of bioclastic carbonate (mudstone, wackestone, packstone, and grainstone) with minor amounts of siliciclastic shale. The dominant lithofacies, in order of importance, are heterolithic laminated carbonate mudstone and siliciclastic shale (lithofacies Cml) which are interpreted as tidalites, massive gray carbonate mudstone (Cmm), massive light gray carbonate mudstone with Stromatactis (Cms), massive bioclastic grainstone (Cgm) which are interpreted as storm layers, massive grainstone with lithoclasts (Cgm) which are interpreted as reworked beachrock, skeletal packstone (Cps), massive dolomicrite (Dmm) and massive dolograinstone (Dgm), alternation of planar laminated carbonate mudstone and wackestone (Cmw), alternation of skeletal packstone and skeletal mud/wackestone (Cpm), alternation of packstone and mudstone (Cmf), and carbonate wackestone (Cws). The presence of tidalites, mudcracks, lithoclasts, shell debris, and storm layers indicate that the Trenton Limestone in Northwestern Ohio was deposited in a peritidal carbonate ramp environment. Three lithofacies associations were the tempestite association lithofacies, back ramp lithofacies associat (open full item for complete abstract)

Committee: James Evans PhD (Advisor); John Farver PhD (Committee Member); Jeffrey Snyder PhD (Committee Member) Subjects: Geology

Master of Science, Miami University, 2017, Geology and Environmental Earth Science

New knowledge regarding epithermal gold from Round Mountain Gold Mine (RMGM) aims to add to what is known about gold mineralization and ore formation. The Type 4 gold ore at RMGM is unusual in that it contains both disseminated gold (nm-µm) and macrocrystalline gold. Unmodified samples of macrocrystalline gold and disseminated gold within bulk ore were acquired from the Type 4 and determined to be texturally and mineralogically distinct. Detailed investigation using field emission scanning electron microscopy (FESEM), coupled with energy dispersive x-ray spectroscopy (EDXS), concluded that gold mineralization began as two-dimensional nucleation following nanoparticle aggregation. The dominant mechanism for mineralization then shifted to adhesive growth, as gold in solution reached levels greater than supersaturation. Results further indicate that two distinct sequences for gold mineralization occurred where only macrocrystalline gold contained paragenetic apatite, goethite, and gold telluride, and pyrite and chlorite were associated strictly with bulk ore. Several of these minerals, especially pyrite, goethite, and chlorite may have significant implications for extraction efficiency using conventional cyanide heap leach. U-Pb dating of apatite was also conducted in attempts to further constrain the deposit's complex mineralization history, but was found to be inaccurate in determining an age date due to insufficient samples.

Committee: Mark P.S. Krekeler (Advisor); John Rakovan (Committee Member); Claire McLeod (Committee Member) Subjects: Earth; Geochemistry; Geology; Mineralogy; Mining; Petrology

Doctor of Philosophy, The Ohio State University, 1979, Graduate School

Committee: Not Provided (Other) Subjects: Geology

Master of Science, Miami University, 2001, Geology and Environmental Earth Science

This thesis consists of two separate but related manuscripts; Surface Structure Controlled Sectoral Zoning of REE in Fluorite from Long Lake, N.Y. and Bingham, N.M. and Mineralogy and paragenetic history of fluorites from Bingham, N.M. Links between REE chemistry, color and morphology. In the first paper, fluorite crystals from two deposits were identified as sectorally zoned with respect to the rare earth elements. It has been shown that the differential incorporation of the REE occurred during crystal growth due to heterogeneities in the atomic structure of the fluorite surface. The second paper addresses the use of the REE as petrogenetic indicators in actual hydrothermal deposits. This study attempts to identify if there is a systematic correlation between REE chemistry and other factors, such as crystal morphology, and color, or if compositional variability merely reflects temporal variation in hydrothermal fluids.

Committee: John Rakovan (Advisor) Subjects: