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Investigation Of Sulphide-Poor Gold Mineralization At The Deep A Zone, Kiena Complex, Québec, Stephanie A. Kobylinski 2022 The University of Western Ontario

Investigation Of Sulphide-Poor Gold Mineralization At The Deep A Zone, Kiena Complex, Québec, Stephanie A. Kobylinski

Electronic Thesis and Dissertation Repository

The Kiena Complex is located halfway between Malartic and Val d’Or in Québec, within the Abitibi Greenstone belt in the Superior Province. This study examined mineralization at the Kiena Complex using detailed core logging, geochemical analysis of wall rock, petrography, EPMA, and gold deportment studies. The analysis and interpretations indicate that the unique sulphide-poor gold-rich quartz veins of the Deep A Zone at the Kiena Complex contain 500 μm2) are located at the contact of quartz and corroded albite grains, and fine gold grains (5-500 μm2) are hosted within the corroded albite.


Connections Between Interglacial Variation And Lithological Variability Within Midland Basin Permian Shale Rocks In Martin County, Texas, Helen Rice Hammon 2022 Louisiana State University at Baton Rouge

Connections Between Interglacial Variation And Lithological Variability Within Midland Basin Permian Shale Rocks In Martin County, Texas, Helen Rice Hammon

LSU Master's Theses

The Upper Pennsylvanian (323.2–289.9 Ma) and Lower Permian (289.9-251 Ma), (Wolfcamp and Spraberry formations) interval of the Midland Basin, West Texas, contains a mixed succession of shale, carbonate, and siltstone/sandstone lithofacies that accumulated in a deep-water marine environment under variable hydrographic restrictions. The heterogenous stratigraphy found in the Wolfcamp and Spraberry formation was formed in response to variations in sea level and a transition from a glacial to an interglacial climate during the Early Permian. These fluctuations left behind alternating beds of mudstone and carbonate, interwoven with thin sandstone beds. Because the Wolfcamp and Spraberry formations are highly heterolithic, it …


Empirical And Modeled Δ13c And Δ15n Isoscapes In The Gulf Of Mexico And Their Application To Fish Eye Lens Migration Studies, Brianna Michaud 2022 University of South Florida

Empirical And Modeled Δ13c And Δ15n Isoscapes In The Gulf Of Mexico And Their Application To Fish Eye Lens Migration Studies, Brianna Michaud

USF Tampa Graduate Theses and Dissertations

Isoscapes are depictions of the spatial patterns of isotopic values in a given area. Isoscapes can be created using measurements form samples (empirical isoscapes) or using statistical models of spatial isotopic variation (modeled isoscapes). Isoscapes have a wide variety of potential applications though, in the realm of marine ecology, they are most often used infer ecological processes, food web linkages, the origin of samples, and the movements of marine organisms.

However, to use isoscapes for these applications, it is necessary to have isoscapes at spatial scales relevant to the application in question. It is also necessary to have isoscapes that …


The Mineralogy And Geochemistry Of Illinois Basin Paleosols: Recognizing Detrital, Pedogenic, And Diagenetic Minerals, Julia A. McIntosh 2022 Southern Methodist University

The Mineralogy And Geochemistry Of Illinois Basin Paleosols: Recognizing Detrital, Pedogenic, And Diagenetic Minerals, Julia A. Mcintosh

Earth Sciences Theses and Dissertations

The geochemical compositions of minerals in paleosols are assumed to be homogenous and attained through chemical weathering processes during episodes of pedogenesis in the geologic past. As such, the geochemical composition of minerals from paleosols may be used to reconstruct ancient climates and environments. One problem with this assumption is that paleosols were initially clastic sedimentary rocks or substrate prior to pedogenesis, thus it is likely that some portion of the paleosol is still composed of detrital minerals. Secondly, conditions may change in a sedimentary basin as the basin is buried and later uplifted, potentially triggering new mineralization or transformation …


Experimental Insights Into The Origin Of Microcrystalline Calcites, Mohammed Hashim 2022 Western Michigan University

Experimental Insights Into The Origin Of Microcrystalline Calcites, Mohammed Hashim

Dissertations

A significant proportion of modern marine calcium carbonate sediments is dominated by metastable aragonite and high Mg calcite that either dissolves or stabilizes to low-Mg-calcite (calcite) or dolomite during diagenesis. Sediment dissolution and stabilization have implications for the CaCO3 budget in the ocean and carbon burial rates. Yet, the diagenetic conditions that promote each process and their relative importance are poorly understood. Further, stabilization most commonly produces calcite microcrystals that exhibit various textures and host micropores. Despite their ubiquity in the rock record, the controls on microcrystal textures remain unclear. Here, laboratory experiments were used to investigate aragonite-to-calcite stabilization as …


Geologic Controls On 137cs Cycling By Terrestrial Vegetation In The Eastern U.S., Kathleen Chellman 2022 William & Mary

Geologic Controls On 137cs Cycling By Terrestrial Vegetation In The Eastern U.S., Kathleen Chellman

Undergraduate Honors Theses

137Cs is a radioactive trace metal (T1/2 = 30 y) that was dispersed globally by nuclear weapons testing in the 1950s-1960s. Prevailing winds and precipitation systems caused some areas far from the test sites to receive significant fallout, which is still easily measured in soils, sediments and even some vegetation in the Eastern United States. Recent work near Chernobyl and Fukushima indicates that trace levels of 137Cs can harm insects, pollination services, and other ecological functions. In areas with low soil potassium, 137Cs is cycled in vegetation; however, soil potassium alone doesn't consistently predict the 137 …


Honey As A Biomonitor For Air Pollutant Deposition In The Eastern United States Using Ion Chromatography And Scanning Electron Microscopy, Cole Cochran 2022 William & Mary

Honey As A Biomonitor For Air Pollutant Deposition In The Eastern United States Using Ion Chromatography And Scanning Electron Microscopy, Cole Cochran

Undergraduate Honors Theses

Anthropogenic activities generate metal, acid, and particulate air pollutants which negatively impact human and ecological health. In the United States, power plant, industrial, and vehicle emissions are leading causes of air pollution, however, the measurement of air pollution at high-resolution spatial regimes remains a challenge. Honey has emerged as a powerful biomonitoring tool to effectively quantify contaminants without the need for a large array of monitoring instruments. I hypothesized that honey could be used to effectively measure and map modern air pollutant spatiotemporal relationships over the Eastern U.S. Using ion chromatography with sulfate as an indicator for air pollution and …


Improving The Hydrological Analysis Of Groundwater Flow Paths By Integrating Geochemical And Physical Characteristics Of A Highly Fractured Aquifer System To Create Sustainable Use Of Groundwater In A Climate With Projected Drying Trends., Marsha K. Allen 2022 University of Massachusetts Amherst

Improving The Hydrological Analysis Of Groundwater Flow Paths By Integrating Geochemical And Physical Characteristics Of A Highly Fractured Aquifer System To Create Sustainable Use Of Groundwater In A Climate With Projected Drying Trends., Marsha K. Allen

Doctoral Dissertations

Improving the hydrological analysis of groundwater flow paths by integrating geochemical and physical characteristics of a highly fractured aquifer system to create sustainable use of groundwater in a climate with projected drying trends. Precipitation over Caribbean islands has decreased steadily since the 1950's, which has led to severe drought conditions. The most recent Pan-Caribbean Drought occurred from 2013 to 2016. Climate models predict that drying trends are expected to continue and become more severe over time as precipitation decreases and temperatures rise. In addition, evaporation rates on these islands are expected to increase by ~15-17%, contributing to the drought. Though …


Contrasting Styles Of Inter-Caldera Volcanism In A Peralkaline System: Case Studies From Pantelleria (Sicily Channel, Italy), Pierangelo Romano, John C. White, Silvio G. Rotolo, Nina J. Jordan, Rosolino Cirrincione, Giovanni De Giorgio, Patrizia Fiannacca, Epifanio Vaccaro 2022 Instituto Nazionale di Geofisica e Vulcanologia (INGV)

Contrasting Styles Of Inter-Caldera Volcanism In A Peralkaline System: Case Studies From Pantelleria (Sicily Channel, Italy), Pierangelo Romano, John C. White, Silvio G. Rotolo, Nina J. Jordan, Rosolino Cirrincione, Giovanni De Giorgio, Patrizia Fiannacca, Epifanio Vaccaro

EKU Faculty and Staff Scholarship

The recent (<190 ka) volcanic history of Pantelleria is characterized by the eruption of nine peralkaline ignimbrites, ranging in composition from comenditic trachyte to comendite to pantellerite. The ~46 ka Green Tuff (GT) was the last of these ignimbrites, which was followed by many effusive and explosive low-volume eruptions of pantellerite from vents within the caldera moat and along the caldera rim. Although recent studies have shed additional light on the age, petrochemistry, and volcanology of the older ignimbrites, there is very little knowledge of magmatism that occurred between these older ignimbrites, primarily due to the very scarce exposures. In this paper, we present new field descriptions and geochemical data for three local peralkaline centers never studied before, two pre-GT and one post-GT, which share a similar setting with respect to the caldera scarps but differ in terms of their age, composition, and eruptive style. These centers include: (i) the older (~125 ka) Giache center (comenditic trachyte), (ii) the ~67 ka Attalora center (comendite, pantellerite), and (iii) the younger (~14 ka) Patite center (pantellerite).


Effects Of Glutamine Deamidation On The Oxygen Isotope Compositions Of Bone Collagen, Curtis W. Russell 2022 The University of Western Ontario

Effects Of Glutamine Deamidation On The Oxygen Isotope Compositions Of Bone Collagen, Curtis W. Russell

Electronic Thesis and Dissertation Repository

The oxygen (O) isotope composition of mammalian collagen has the potential to provide information about the drinking water and hence geographic location and climate during the life of modern and ancient animals. An accurate and reproducible O-isotope analysis of collagen, however, has been elusive. Here, the O-isotope compositions of collagen from cortical bone of four megaherbivores were compared using two extraction procedures: the traditional Longin (HCl) method and the less commonly employed EDTA method. Preservation of O-isotope compositions was evaluated by measuring collagen peptide-chain masses, specifically the glutamine deamidation level (GDL). The EDTA method yielded collagen with a GDL of …


Stratigraphic And Geochemical Evaluation Of Distal Flows Of The Columbia River Flood Basalts In The Greater Vale Area, Southeastern Oregon, Lena Marie Fox 2022 Portland State University

Stratigraphic And Geochemical Evaluation Of Distal Flows Of The Columbia River Flood Basalts In The Greater Vale Area, Southeastern Oregon, Lena Marie Fox

Dissertations and Theses

Exposures of Columbia River Basalt Group (CRBG) in southeastern Oregon are dominated by the four main phase CRBG units: Steens Basalt, Imnaha Basalt, Grande Ronde Basalt (GRB), and Picture Gorge Basalt (PGB). These units are best seen in stratigraphic sequence along the Malheur Gorge corridor of southeastern Oregon, between the towns of Vale and Juntura, with flows of Steens Basalt from the south overlain by flows of Imnaha and GRB from the north. Recently, PGB flows were found to be part of the eastern Malheur Gorge stratigraphy as well.

In Malheur Gorge, local units of Birch and Hunter Creek Basalt …


Geologic Homogenization, Conditioning, & Reuse, University of North Dakota. Energy and Environmental Research Center 2022 University of North Dakota

Geologic Homogenization, Conditioning, & Reuse, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about the Energy & Environmental Research Center (EERC) project to evaluate the geologic homogenization, conditioning, and reuse (GHCR) concept of water management. Describes the GHCR concept and summarizes results of the multiyear project.


Fundamental Controls On The Water Cycle In Arid Environments: A Mechanistic Framework For Spatiotemporal Connectivity Between Hydroclimate And Groundwaters In The Dry Andes, Brendan J. Moran 2022 University of Massachusetts Amherst

Fundamental Controls On The Water Cycle In Arid Environments: A Mechanistic Framework For Spatiotemporal Connectivity Between Hydroclimate And Groundwaters In The Dry Andes, Brendan J. Moran

Doctoral Dissertations

There remain many persistent uncertainties regarding fundamental aspects of natural water cycles in arid mountainous regions, the Dry Andes of South America represents one of the most extreme examples of these environments on the Planet. Deep water tables (>100 meters), long groundwater transit times and distances (>100 years, 10-100 kilometers), limited and infrequent rainfall, remote and difficult to access terrain, and complex salar/evaporite hydrogeology common in these environments make reliable monitoring of these hydrological systems particularly difficult. As a result, major gaps remain in our understanding of critical aspects of the water cycle such as recharge and evaporation …


Distribution Of Particulate Organic Carbon – Fluxes And Inventories – In Growth-Faulted Coastal Wetlands, Samuel Joel Whitehead 2022 University of Kentucky

Distribution Of Particulate Organic Carbon – Fluxes And Inventories – In Growth-Faulted Coastal Wetlands, Samuel Joel Whitehead

Theses and Dissertations--Earth and Environmental Sciences

Coastal wetlands along the Northern Gulf of Mexico (NGOMx) are critically important but threatened environments which provide significant and diverse economic, social, and environmental value. These environments are essential components to the global carbon cycle, serving as one of the most efficient terrestrial carbon sinks. Since onset of the Industrial Revolution increasing rates of coastal wetland loss have been documented due to a variety of anthropogenic activities, neotectonic processes, subsidence, and rising sea-levels. This research utilized an array of methods and sedimentological analyses to test the hypothesis that growth-fault induced changes at Earth’s surface affects the delivery to, and storage …


Impact Of Prairie Restoration On Geochemistry And Microbial Communities In Groundwater, Kayla Koenig 2022 Northern Illinois University

Impact Of Prairie Restoration On Geochemistry And Microbial Communities In Groundwater, Kayla Koenig

Graduate Research Theses & Dissertations

Prairie restoration is important for reversing the loss of biodiversity and repairing ecosystem functions humanity is dependent on diverse ecosystems. This study looks at the impact of the beginning phases of prairie restoration on groundwater geochemistry and microbial communities the relationship between them. This research project studied the geochemistry and microbial communities in five wells before, during, and after the beginning phases of the first year of a prairie restoration on the Northern Illinois University campus. Water samples were collected bimonthly for a year and analyzed on an Ion Chromatograph. Microbial samples were collected monthly and underwent DNA extraction, amplification, …


Exceptional Agate Formation Found In Spokane Basalt, Matthew J. Markus 2022 Eastern Washington University

Exceptional Agate Formation Found In Spokane Basalt, Matthew J. Markus

2022 Symposium

People don’t normally associate semi-precious gems with basalt or the “boring black rock” that dominates the Eastern Washington landscape. However, a site just northeast of Cheney in the West Planes of Spokane, shows where a system of gem-filled veins can be found nestled into the 16-million-year-old (Kasbohm and Schoene, 2018) Priest Rapids Member of the Wanapum Basalt that is a part of the greater Columbia River Basalt. The volcanic rocks are the host to millimeter - 10 cm wide fractures with variable colored agate and opal.


Structural And Petrologic Insights Into The Emplacement Of Effusive Silicic Lavas: Inyo Domes, California, Shelby L. Isom 2022 West Virginia University

Structural And Petrologic Insights Into The Emplacement Of Effusive Silicic Lavas: Inyo Domes, California, Shelby L. Isom

Graduate Theses, Dissertations, and Problem Reports

The Long Valley volcanic region, eastern California, USA is most famous for the caldera-forming eruption which produced the Bishop Tuff ~760,000 years ago. Over the last 3,000 years volcanism has been focused in the western margin of the region through punctuated eruptions of silicic lavas and domes. Three simultaneous effusive silicic eruptions, ~600 years ago, generated three lava domes: Obsidian Dome; Glass Creek Dome; and Deadman Dome which erupted onto vastly different topographies. These domes are exceptionally unique as they erupted variable amounts of two textural and chemical endmember lavas (crystal-rich and crystal-poor) that intimately mixed. The overarching goal of …


Assessing Assumptions And Applying Cosmogenic Nuclide Methods To Earth Surface Processes, Christopher T. Halsted 2022 University of Vermont

Assessing Assumptions And Applying Cosmogenic Nuclide Methods To Earth Surface Processes, Christopher T. Halsted

Graduate College Dissertations and Theses

Terrestrial in situ cosmogenic radionuclides are powerful tools for quantifying rates and durations of Earth surface processes. Among the many applications of cosmogenic radionuclides are quantification of basin-scale erosion rates, burial durations of paleosols and terrace sediments, and unraveling of glacial chronologies. In this dissertation I use large data sets to investigate methodological assumptions critical for using cosmogenic radionuclides to interpret Earth surface processes, and I apply this isotope system to reconstruct the deglacial history of the Laurentide Ice Sheet in the northeastern United States.

I use new and previously-published measurements of in situ 26Al and 10Be concentrations, over 300 …


The Effects Of Channel Incision And Land Use On Surface-Water/Groundwater Interactions In The Teanaway River Basin, Washington, Usa, Joseph Petralia 2022 Central Washington University

The Effects Of Channel Incision And Land Use On Surface-Water/Groundwater Interactions In The Teanaway River Basin, Washington, Usa, Joseph Petralia

All Master's Theses

The Teanaway River basin, a major tributary to the Yakima River, is host to several restoration projects with the intention of returning the river channel to a more natural state and improving riparian habitat. These projects may also increase aquifer storage and potentially increase summertime streamflows. This study of the Teanaway Valley Family Farm, an 88-hectare parcel on the main-stem Teanaway River that was recently purchased by Washington Department of Fish and Wildlife, provides hydrogeologic data that will inform these restoration projects. Following the purchase of this land, ten wells were installed within and slightly above the floodplain in order …


Pascoite Minerals And Potential Application Of Nmr Spectroscopy, Craig C. McLauchlan, Beth Trent-Ringer, Debbie C. Crans 2022 Illinois State University

Pascoite Minerals And Potential Application Of Nmr Spectroscopy, Craig C. Mclauchlan, Beth Trent-Ringer, Debbie C. Crans

Faculty Publications – Chemistry

The 20 minerals encompassing the pascoite family of decavanadate isopolyanion-containing [V10O28]6− minerals include a few minerals, such as rakovanite, that have been described as containing a protonated decavanadate anion. Rakovanite was originally assigned the formula Na3[H3V10O28]•15H2O and now is redefined with an ideal formula (NH4)3Na3[V10O28]•12H2O. Nuclear magnetic resonance (NMR) and particularly 51V NMR spectroscopy is an informative method used to describe the protonation state and speciation in both solid and solution states …


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