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Articles 31 - 60 of 198
Full-Text Articles in Geology
Understanding The Connection Between Gypsum Blooms And Human Health At The Salton Sea, Isabel Ichiyama
Understanding The Connection Between Gypsum Blooms And Human Health At The Salton Sea, Isabel Ichiyama
Undergraduate Honors Theses
The Salton Sea is a closed hypersaline lake in Southern California that has been receiving little input over the past few decades, leading to desiccation that is rapidly increasing every year. This large-scale evaporation of the sea has led to increased dissolved solutes, high salinity, and gypsum blooms. Gypsum blooms, the precipitation of gypsum (CaSO42H2O) in the sea, have been a prominent facet of the sea and their distribution is well known. However, much of their chemistry and potential health hazards are still undetermined. Potential health effects from gypsum salt, an atmospheric dust particle present at the sea, have known …
The Impact Of Glacial Proximity On The Elemental Composition Of Leachate Derived From Sediment Weathering, Karoline Ford
The Impact Of Glacial Proximity On The Elemental Composition Of Leachate Derived From Sediment Weathering, Karoline Ford
Theses/Capstones/Creative Projects
This study assesses chemical weathering trends as they relate to glacial retreat. The chemical environment of surfaces exposed to the atmosphere differs significantly from beneath a glacier. As a glacier melts, changes to the biogeochemical processes generate environmental gradients. This study analyzed chemical weathering signals at different distances from a glacial front by comparing the elemental composition of leachate derived from sediments in southeastern Greenland. Samples from proglacial, nonglacial, and moraine locations were weathered in a laboratory setting, and ion chromatography was used to determine the elemental composition of the products. Divergent trends in leachate composition were observed as distance …
Modeled Uranium Series Disequilibria In A Heterogeneous Mantle Underlying Iceland, Dana Andersen
Modeled Uranium Series Disequilibria In A Heterogeneous Mantle Underlying Iceland, Dana Andersen
Honors Program: Senior Projects (Public)
Regional lithologic heterogeneities in Earth’s mantle may significantly contribute to variations in magma productivity and crustal generation. Such heterogeneities may be a key factor in the anomalously high rates of magmatism and thickened crust of Iceland, which are not fully explained by the presence of a mantle plume. However, the exact lithologic composition of the mantle underlying Iceland is largely unknown. Recent trace element modeling has suggested a two-component melt source beneath Iceland, consisting of a typical upper mantle peridotite mixing with one of several compositions of pyroxenitic material. This study further investigates these potential melt sources by calculating U-series …
Study Of Trace Elements In Southern Nevada Spring Waters And Lakes, Hyejeong Lee
Study Of Trace Elements In Southern Nevada Spring Waters And Lakes, Hyejeong Lee
UNLV Theses, Dissertations, Professional Papers, and Capstones
Comprehending the natural water resource is imperative for the entire state of Nevada and of particular significance for Southern Nevada, where rapid population growth and climate change are placing significant strain on supplies. This research underscores the significance of water chemistry in identifying potential water source areas through trace elements. For the first time, the study proposed measuring the compositions of the entire suite of metal elements, ranging from Li to U, in over 40 springs in the Moapa Valley and its upper gradient valleys, utilizing the iCAP Qc ICP-MS (Inductively Coupled Plasma Mass Spectrometer) at UNLV. The research evaluated …
Dynamics And Timescales Of Magmatic Processes At Cerro Uturuncu, Bolivia, Sarah Jane Rasor
Dynamics And Timescales Of Magmatic Processes At Cerro Uturuncu, Bolivia, Sarah Jane Rasor
Graduate Theses/Dissertations
Between 12-25°S latitude there is prolific volcanism fueled by the Altiplano-Puna Magmatic Body (APMB), a mid-crustal magma body above the 30° angle subduction of the Nazca plate and within 60-70 km thick South American crust. Cerro Uturuncu, a stratovolcano constructed above the center of the APMB, can provide insight to the evolution of the APMB over time. Previous research suggests that the APMB is more homogenous near its center as opposed to its edges. However, the processes that led to greater homogenization as well as the structure of the magma body below Cerro Uturuncu remain unknown. This research contributes greater …
Magmatic Evolution Of The Chasca Orkho Lava Series And Its Magmatic Enclaves, Volcán Ollagüe, Central Andes, Nathaniel W. Lenhard
Magmatic Evolution Of The Chasca Orkho Lava Series And Its Magmatic Enclaves, Volcán Ollagüe, Central Andes, Nathaniel W. Lenhard
Graduate Theses/Dissertations
Magma mixing is a common factor in the creation of intermediate composition magmas and a potential instigator of a volcanic eruption. Magmatic enclaves, physical evidence of magma mixing within a volcanic system, are a phenomenon whose mechanisms remain unclear and debated. Common hypotheses explaining the occurrence of magmatic enclaves within a host lava range from the repeated injection of a new magma into a shallow reservoir to the disruption of equilibrium within a stratified magma chamber. Within the Andean Central Volcanic Zone (CVZ), the occurrence of magmatic enclaves yields similar geochemical compositions to their respective host rocks, bringing more difficulty …
Petrological And Geochemical Evaluation Of Rare-Earth Element Potential In The Sparta Granite Complex, Max J. Eshbaugh
Petrological And Geochemical Evaluation Of Rare-Earth Element Potential In The Sparta Granite Complex, Max J. Eshbaugh
Honors College Theses
Rare earth elements (REEs) are important resources with applications in the electronics, renewable energy, and automotive industries. REEs may be concentrated in the residual weathered portion of igneous parent rocks, typically granites. These residual deposits are mined in southeast Asia, but analogous climatic and geologic conditions suggest the existence of economically viable REE residual deposits in the southeastern United States (U.S.). The Sparta Granite Complex in east-central Georgia is a granitoid complex emplaced at the end of the Alleghanian orogeny, forming a suture between the Savannah River and Milledgeville terranes. Petrologic and geochemical assessments of the Sparta Granite and overlying …
Geochemical Analysis Of Recent Volcanic Ash Blanketing Barbados And Constraints On Magma Composition (V32e-0112), Nazrul I. Khandaker, Krishna Mahabir, Surendranauth Mahabir, Lloyd Kiefer, Juan C. Campo, Andrew M. Singh
Geochemical Analysis Of Recent Volcanic Ash Blanketing Barbados And Constraints On Magma Composition (V32e-0112), Nazrul I. Khandaker, Krishna Mahabir, Surendranauth Mahabir, Lloyd Kiefer, Juan C. Campo, Andrew M. Singh
Publications and Research
Preliminary field and geochemical investigations were conducted on ash samples from Barbados to chemically characterize and decipher magma chemistry associated with a recent volcanic event. A thick plume of volcanic ash from the La Soufriere Volcano in St Vincent, which erupted on April 9, 2021, caused lower visibility due to ash clouds which engulfed the region for some time. Three authors from the research team visited Barbados during the summer subsequent and completed a reconnaissance investigation on recent ashfall. St Vincent is a small volcanic island in the Eastern Caribbean and lies in the southern part of the Lesser Antilles …
Geochemical Characterization Of The Louann Salt, Puma Field, Green Canyon, Gulf Of Mexico Basin – Using Xrf And Xrd, Brian Lesh
Electronic Theses and Dissertations
The Jurassic-aged Louann Salt is an evaporite sequence deposited in the Gulf of Mexico Basin (GOMB). It is an important component of the GOMB petroleum system and influences the facies pattern in overlying strata and the distribution of petroleum stratigraphic traps. The Louann Salt is composed primarily of halite with intercalated anhydrites and silty or sandy-halite intervals, with overall thicknesses in excess of four kilometers (~13,000 feet). Suture zones occur intermittently within the Louann Salt, formed by the collision of allochthonous evaporite layers. The mineralogy and geochemistry of the suture zones are currently understudied and can be hazardous during drilling …
Geochemical Characterization Of The Bone Spring Formation, Delaware Basin, Using Chemostratigraphy And Integrated Petrophysics, David Tonner
Geochemical Characterization Of The Bone Spring Formation, Delaware Basin, Using Chemostratigraphy And Integrated Petrophysics, David Tonner
Electronic Theses and Dissertations
The Delaware Basin forms part of West Texas's and New Mexico’s famous petroleum-generating Permian Basin. The Bone Spring Formation is a prolific hydrocarbon producer within this basin, creating one of the world’s richest oil shales. This formation has lithological sequences that are characterized by repeating carbonate and siliciclastic intervals of a third-order cycle which can largely be correlated to highstand and lowstand systems tracts, respectively. Lithological complexity and facies change are manifested by debris flows, turbidites, and slumps. In addition to glacio-eustasy, both tectonism and broader Milankovitch cycles have influenced the depositional history. Previous investigations have utilized cores and wireline …
Ice Deposits In Lava Tubes From West-Central New Mexico As Archives Of Past Volcanic Eruptions And Climate Change, Quinton Z. Vitelli-Hawkins
Ice Deposits In Lava Tubes From West-Central New Mexico As Archives Of Past Volcanic Eruptions And Climate Change, Quinton Z. Vitelli-Hawkins
USF Tampa Graduate Theses and Dissertations
The Southwest of the United States is currently in a megadrought phase. Recent studies have shown that three of the most severe droughts of the last two millennia have occurred in the last 120 years, while geo-archaeological evidence suggests there were five megadroughts just from 150 to 950 CE. To try to better understand the causes of the droughts across the Southwest, a 110-cm long ice core was drilled from an ice deposit in a lava tube (Cave 29) from El Malpais National Monument in west-central New Mexico. The δ18O values in the ice core (ranging from −11.78 to −3.54‰) …
Connections Between Interglacial Variation And Lithological Variability Within Midland Basin Permian Shale Rocks In Martin County, Texas, Helen Rice Hammon
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 …
Connections Between Interglacial Variation And Lithological Variability Within Midland Basin Permian Shale Rocks In Martin County, Texas, Helen Rice Hammon
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 …
Geology And Geochronology Of The East Dome Complex Within The Hog Heaven Volcanic Field, Flathead County, Montana, Ethan Coppage
Geology And Geochronology Of The East Dome Complex Within The Hog Heaven Volcanic Field, Flathead County, Montana, Ethan Coppage
Graduate Theses & Non-Theses
This study describes the style and timing of volcanic activity and mineralization in the East Dome Complex (EDC) of the 55-km2 Eocene-Oligocene Hog Heaven Volcanic Field (~36-30 Ma; HHVF) located in northwestern Montana. The HHVF consists of three NE-aligned, predominantly high-K rhyodacitic dome complexes (1.8-4.9 wt. % K2O; 63.2-72.9 wt. % SiO2) formed near the crest the Purcell Anticlinorium, a major Cordilleran fold-thrust belt structure deforming metasedimentary rocks of the Mesoproterozoic Belt Supergroup. Dome emplacement was controlled by a NE-striking fault associated with a pull-apart basin formed between two overlapping, NW-trending dextral oblique-slip faults. The objective of this study is …
Stratigraphic And Geochemical Evaluation Of Distal Flows Of The Columbia River Flood Basalts In The Greater Vale Area, Southeastern Oregon, Lena Marie Fox
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 …
Using Lake Sediment Chemistry In The Exploration For Nickel Laterite Deposits In Tropical Regions, Gabriela Yvonne Ramirez
Using Lake Sediment Chemistry In The Exploration For Nickel Laterite Deposits In Tropical Regions, Gabriela Yvonne Ramirez
Masters Theses
"Developing reliable geochemical indicators to guide the search for ore deposits is a long-standing goal. This particularly applies to tropical regions that are often heavily vegetated which hampers boots-on-the ground exploration efforts. Here we present the preliminary results of a study that investigates the usefulness of lake sediment chemistry in the exploration for nickel laterite ore deposits in tropical regions using Lake Izabal, Guatemala, as a case study. Lake Izabal’s catchment area contains Ni laterite deposits along its northern shore, whereas no Ni-laterite discoveries have been made in the south except for a Ni mine in the southern region that …
Chemical And Thermal Influence On Intermediate Magma Storage Conditions: Volcán Ollagüe, Chile-Bolivia, Central Andes, Drew Allen Laviada-Garmon
Chemical And Thermal Influence On Intermediate Magma Storage Conditions: Volcán Ollagüe, Chile-Bolivia, Central Andes, Drew Allen Laviada-Garmon
Graduate Theses/Dissertations
Continental arc volcanoes are the single best portrayal of the evolution of recycled earth material stemming from subduction, one of the most important and foundational phenomena in global tectonics. Understanding the genesis of intermediate-composition magmas produced at arc volcanoes is a difficult process making them a focal point for investigation. Geochemical investigation of zircon and plagioclase mineral phases erupted from continental arcs can provide insight into magma process, generation, storage conditions, timescales and differentiation of sub-volcanic plumbing systems prior to eruption events. The Central Volcanic Zone is a prime example of continental arc volcanism through subduction, and is host to …
Geochemical And Sensor-Based Monitoring Of Fault-Associated Carbonic Springs In Grand Canyon And Northern New Mexico: Identifying Hydrologic Pathways And Establishing Baselines, Chris Mcgibbon
Earth and Planetary Sciences ETDs
This dissertation examines the interaction of spring systems and faulting. When springs discharge within a fault zone the interaction is often complex, and multiple methods are required to understand the flow, mixing and evolution of groundwater. In karst aquifer systems fracture networks can range from sub-millimeter to meters and only adds to the complexities involved in examining spring hydrology. The Interest in springs and faulting is not only driven by science, but also has applied applications. Faulting and fluid flow are of interest to the oil and gas industry, and potential CO2 sequestration. In the southwestern US, water quantity …
Identifying Biogeochemical Factors Responsible For The Cyclical Precipitation Of Sphalerite And Galena In Low Temperature Mississippi Valley Type Ore Deposits, Daniel John Makowsky
Identifying Biogeochemical Factors Responsible For The Cyclical Precipitation Of Sphalerite And Galena In Low Temperature Mississippi Valley Type Ore Deposits, Daniel John Makowsky
Theses and Dissertations
Mississippi Valley Type (MVT) lead and zinc deposits provide a significant source of sedimentary galena and sphalerite. However, geochemical characteristics and genesis including the source and production of hydrogen sulfide required for galena and sphalerite ore formation and the reasoning for quick, episodic mineralization is not fully understood. By simulating regional MVT brines, the input and effect of biological by-products during the development of these ores as well as the cause of cyclicity within MVT deposits have been observed. Experiments using compositions from MVT fluid inclusions were conducted over two-week periods. Variables during the experiments included temperature, CO2, hydrogen sulfide …
Geochemical Investigation Of Monogenetic Volcanoes From The Pribilof Islands, Bering Sea, Alaska, Clayton L. Reinier
Geochemical Investigation Of Monogenetic Volcanoes From The Pribilof Islands, Bering Sea, Alaska, Clayton L. Reinier
Graduate Theses/Dissertations
Small-volume basaltic magmas found at continental intraplate environments have not been as extensively studied compared to their polygenetic counterparts. Specifically, regions such as the Bering Sea basalt province, described as a diffuse igneous province, have commonly been overlooked. Assumptions that these systems are invoked by simple, single batches of magma has subsequently left a gap in understanding the processes responsible for primary magma generation away from plate boundaries with little tectonic influence. The following studies that constitute this thesis focus on an in-depth geochemical investigation at the crystal and sub-crystal scale to evaluate lithospheric mantle heterogeneities, processes that govern primary …
The Sedimentary Geochemistry And Paleoenvironments Project, Úna C. Farrell, Rifaat Samawi, Savitha Anjanappa, Roman Klykov, Oyeleye O. Adeboye, Heda Agic, Anne Sofie C. Ahm, Thomas H. Boag, Fred Bowyer, Jochen J. Brocks, Tessa N. Brunoir, Donald E. Canfield, Xiaoyan Chen, Meng Cheng, Matthew O. Clarkson, Devon B. Cole, David R. Cordie, Peter W. Crockford, Huan Cui, Tais W. Dahl, Lucas D. Mouro, Keith Dewing, Stephen Q. Dornbos, Nadja Drabon, Julie A. Dumoulin, Joseph F. Emmings, Cecilia R. Endriga, Tiffani A. Fraser, Robert R. Gaines, Richard M. Gaschnig, Timothy M. Gibson, Geoffrey J. Gilleaudeau
The Sedimentary Geochemistry And Paleoenvironments Project, Úna C. Farrell, Rifaat Samawi, Savitha Anjanappa, Roman Klykov, Oyeleye O. Adeboye, Heda Agic, Anne Sofie C. Ahm, Thomas H. Boag, Fred Bowyer, Jochen J. Brocks, Tessa N. Brunoir, Donald E. Canfield, Xiaoyan Chen, Meng Cheng, Matthew O. Clarkson, Devon B. Cole, David R. Cordie, Peter W. Crockford, Huan Cui, Tais W. Dahl, Lucas D. Mouro, Keith Dewing, Stephen Q. Dornbos, Nadja Drabon, Julie A. Dumoulin, Joseph F. Emmings, Cecilia R. Endriga, Tiffani A. Fraser, Robert R. Gaines, Richard M. Gaschnig, Timothy M. Gibson, Geoffrey J. Gilleaudeau
Geosciences: Faculty Publications
No abstract provided.
Major Controls On Diagenesis In The Martin Bridge Formation: Wallowa Mountains, Oregon, Jane Lyra Eisenberg
Major Controls On Diagenesis In The Martin Bridge Formation: Wallowa Mountains, Oregon, Jane Lyra Eisenberg
Dissertations and Theses
Diagenetic alteration in carbonates has long frustrated scientists who wish to use their chemistry and/or texture to understand conditions at the time of deposition. Though indicators of diagenesis are well documented, their interpretation is not always straightforward. Despite the large volume of research on the subject, the positive identification and interpretation of diagenesis is a source of ongoing debate in the scientific community.
The goal of this study is to better understand the timing of, and controls on, diagenetic alteration in the Martin Bridge Formation (MBF), a Triassic-aged limestone that was altered following deposition. Thirty-nine samples of MBF with differing …
Mid-Miocene Icelandites Of Eastern Oregon: Petrogenesis And Magmatic Lineage To Main-Phase Crbg With Constraints On Storage Sites, Melissa Aileen Carley
Mid-Miocene Icelandites Of Eastern Oregon: Petrogenesis And Magmatic Lineage To Main-Phase Crbg With Constraints On Storage Sites, Melissa Aileen Carley
Dissertations and Theses
The La-Grande Owyhee eruptive axis is a mid-Miocene to Pliocene ~300 km long volcanic belt located at the eastern margin of the Columbia River Basalt Group (CRBG) in Oregon. Within this volcanic belt there are numerous vents that have produced a large volume of petrologically diverse rocks ranging from the tholeiitic flood basalts of the CRBG to rhyolitic tuffs of caldera complexes such as the Lake Owyhee Volcanic field. Icelandites, which are iron rich andesites, are known to occur in association with silica saturated to oversaturated tholeiitic basalts as a minor part of continental flood basalt volcanism. This study investigates …
Geologic Characterization Of The Nonconformity Interface Using Outcrop And Drillcore Analogs: Implications For Injection-Induced Seismicity, Kayla Smith
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Starting around 2009, a greater number of earthquakes than anticipated have occurred in the midcontinent region of the United States. These earthquakes have been linked to increased rates and volumes of wastewater injection at several km’s depth into the Earth’s crust near a contact between crystalline metamorphic or igneous rock and overlying sedimentary rock, known as a nonconformity. While much is known about why these new earthquakes occur, comparatively little is known about the physical and chemical rock properties because the nonconformity contact is primarily buried under km’s of sedimentary rock in the midcontinent region. These rock properties are important …
Petrology And Geochemistry Of Evolved Achondrites: Planetesimal Mantles And Crusts, Zoltan Vaci
Petrology And Geochemistry Of Evolved Achondrites: Planetesimal Mantles And Crusts, Zoltan Vaci
Earth and Planetary Sciences ETDs
Melting and differentiation are fundamental to early solar system evolution on planetary bodies that accreted enough material to heat up radioactively or through impacts and breach their solidi. Partially and fully melted material is present in the meteorite record in the form of primitive achondrites and achondrites, which are fragments of planetesimals that underwent heating events in the first few million years of solar system history. Although the vast majority of this material is mafic or ultramafic, new evolved samples, recovered in the last few decades, are pushing the petrologic and geochemical boundaries of planetesimal melting, differentiation, and crust formation. …
Past Ice-Ocean Interactions On The Sabrina Coast Shelf, East Antarctica: Deglacial To Recent Paleoenvironmental Insights From Marine Sediments, Kara J. Vadman
Past Ice-Ocean Interactions On The Sabrina Coast Shelf, East Antarctica: Deglacial To Recent Paleoenvironmental Insights From Marine Sediments, Kara J. Vadman
USF Tampa Graduate Theses and Dissertations
The East Antarctic Ice Sheet (EAIS) contains ~53 meters of sea level equivalent (SLE) ice, and observations suggest it is sensitive to ongoing and past climate change. The EAIS has traditionally been considered insensitive to climate perturbations because it is largely grounded above sea level. However, aerogeophysical surveys, oceanographic observations, and models indicate that large areas of the EAIS are grounded below sea level and contain 19.2 m SLE. Marine-based parts of the EAIS are thought to be located on inland-sloping beds that drain through marine terminating outlet glaciers, indicating large areas of the EAIS may be more sensitive to …
Petrogenesis Of Hawaiian Lavas: Investigations Using Radiogenic And Non-Traditional Stable Isotopes, Christopher Defelice
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 …
Stratigraphy And Geochemistry Of Paleocene-Aged Bauxites From North Mississippi, Timothy Brendan Clark
Stratigraphy And Geochemistry Of Paleocene-Aged Bauxites From North Mississippi, Timothy Brendan Clark
Electronic Theses and Dissertations
Bauxite is a heavily-mined aluminum ore that forms through the relative depletion of silica to aluminum. In North Mississippi, bauxite occurring within the Upper Midway and Lower Wilcox groups has been the subject of study for over a century. Despite the abundance and duration of research, controversy surrounds the subjects of bauxite genesis and economic value. The last detailed study of North Mississippi bauxite was in the 1980’s, so the goal of this project is to apply newly available technologies and modern hypotheses on bauxite formation to refine and obtain new data. Fieldwork observations yielded pisoliths, horizonation, and possible rhizoliths, …
Variations In Produced Water Chemistry And Relation To Regional Geology And Production In The Marcellus Shale, Northcentral West Virginia, Jonathan M. Brady
Variations In Produced Water Chemistry And Relation To Regional Geology And Production In The Marcellus Shale, Northcentral West Virginia, Jonathan M. Brady
Graduate Theses, Dissertations, and Problem Reports (ETD)
An investigation of 74 Marcellus Shale wells across northcentral West Virginia indicates changes in produced water chemistry and quantity can be related to geologic conditions based on well logs and core data. These changes are determined by reviewing multiple produced water analyses for individual wells for periods up to ten years. Results show variations among the areas in this study. From west to east across central Harrison County to central Taylor County, then north into Monongalia County, gamma-ray logs show increasing intensity, especially in the middle and lower Marcellus. XRD mineralogy from core data shows increasing clay content from west …
Alteration Reactions In A Hornblende-Biotite-Anthophyllite-Fluid System: Implications For Cu-Au Ore Deposits, James Mitchell Lightner
Alteration Reactions In A Hornblende-Biotite-Anthophyllite-Fluid System: Implications For Cu-Au Ore Deposits, James Mitchell Lightner
Graduate Research Theses & Dissertations
High-grade porphyry Cu-Au ore deposits are typically contained in the potassic alteration zone, which forms through the alteration of preexisting country rock by a magmatic volatile phase (MVP) exsolved from an igneous intrusion. The MVP is a H2O dominant phase that contains high concentrations of NaCl, KCl, FeCl2, HCl, sulfur (as H2S or SO2) and minor concentrations of metals. The minerals in the potassic alteration zone are predominantly K-feldspar and biotite with a shreddy texture. Shreddy biotite forms from the replacement of prismatic-tabular shaped hornblende crystals, resulting in a characteristic shreddy texture. The alteration of hornblende to biotite can neutralize …