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Theses/Dissertations

2016

Geochemistry

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Full-Text Articles in Physical Sciences and Mathematics

Geologic And Geochemical Characterization Of Cross-Communication Potential Within The Northern Edwards Aquifer System, Texas, Ingrid J. Eckhoff Dec 2016

Geologic And Geochemical Characterization Of Cross-Communication Potential Within The Northern Edwards Aquifer System, Texas, Ingrid J. Eckhoff

Electronic Theses and Dissertations

The Edwards Aquifer is a large, complex groundwater system located throughout Central Texas in association with the Balcones Fault Zone. The San Antonio and Barton Spring segments of the Edwards Aquifer have been extensively studied in the past because they provide groundwater resources to the largely urbanized areas of San Antonio and Austin, respectively, and smaller communities along the Interstate 35 corridor. Previous research has been conducted on these southern and central portions of the Edwards Aquifer system, which have characterized the structural, hydrogeological and geochemical variations within the highly karsted region. However, the Northern Segment of the Edwards Aquifer …


An Evaluation Of The Lithologies And Geochemistry Of The Upper Beaver Deposit Of The Kirkland Lake Area, Katherine E. Feick Dec 2016

An Evaluation Of The Lithologies And Geochemistry Of The Upper Beaver Deposit Of The Kirkland Lake Area, Katherine E. Feick

Electronic Thesis and Dissertation Repository

The Upper Beaver Cu-Au deposit contains a unique style of mineralization in the Larder Lake and Kirkland Lake areas in terms of mineralization, alteration style, and age. This study aims to use company-provided data, supplemented with focused data collection, to evaluate what information can be attained from company-provided geochemical data. The evaluation uses a combination of hand sample, petrographic, geochemical, statistical, and microprobe analytical methods.

Lithogeochemical analyses indicated that the altered igneous host rock is calc-alkaline in composition and is most likely part of the diorite-monzonite suite. Further, exploratory data analysis of Au and Cu mineralization identified that there are …


Geothermometry Of Two Cascade Geothermal Systems, Donnel Alexander Malkemus Dec 2016

Geothermometry Of Two Cascade Geothermal Systems, Donnel Alexander Malkemus

Dissertations and Theses

For this thesis I applied classical and multi-component geothermometry techniques to new water chemistry data from Breitenbush Hot Springs, Oregon and the Wind River Valley, Washington. A total of 20 well, spring, and stream samples from Breitenbush Hot Springs and 4 spring samples from the Wind River Valley were collected and analyzed for major, minor, and select trace anions and cations, as well as stable oxygen and hydrogen isotopes. I used two computer programs, GeoT and RTEst, to conduct multi-component geothermometry reservoir condition estimation on each water sample. Water chemistry data from Breitenbush Hot Springs indicates a range of thermal, …


Sedimentology And Geochemistry Of The Mixed Carbonate-Siliciclastic Espanola Formation, Paleoproterozoic Huronian Supergroup, Bruce Mines-Elliot Lake Area, Ontario, Canada, Mansour H. Al-Hashim Dec 2016

Sedimentology And Geochemistry Of The Mixed Carbonate-Siliciclastic Espanola Formation, Paleoproterozoic Huronian Supergroup, Bruce Mines-Elliot Lake Area, Ontario, Canada, Mansour H. Al-Hashim

Electronic Thesis and Dissertation Repository

The Espanola Formation of the Paleoproterozoic Huronian Supergroup is a mixed carbonate-siliciclastic succession. Detailed sedimentological analysis of the formation in the Bruce Mines-Elliot Lake region reveals 17 sedimentary lithofacies, which comprise three distinct lithofacies associations. The lithofacies associations represent, in ascending order, shoreface, offshore, and nearshore (or lagoon) depositional environments along a wave- and storm-dominated shallow siliciclastic marine shelf. Major, trace, and rare earth element analyses of the siliciclastic component indicate derivation from a mainly granodioritic Archean upper continental crust with some contributions from mafic volcanic and/or sedimentary rocks. The results show that the source rocks were subjected to relatively …


Geochemical Constraints Of The Gold Mineralization Sources From The South Mine Complex And The Main/’04 Breaks, Macassa Mine, Kirkland Lake, Ontario, Liana K.T. Stammers Nov 2016

Geochemical Constraints Of The Gold Mineralization Sources From The South Mine Complex And The Main/’04 Breaks, Macassa Mine, Kirkland Lake, Ontario, Liana K.T. Stammers

Electronic Thesis and Dissertation Repository

Kirkland Lake Gold’s Macassa Mine is a lode gold deposit in the Abitibi Greenstone. It has two systems of mineralization: the Main/’04 Breaks, and the South Mine Complex (SMC). The objective of this work was to constrain mineralization sources between these systems using geochemical signatures. The SMC has different structure, mineralogy, alteration, trace- and major-elements composition, and δ18O values. The Main/’04 is a series of faults with thin alteration dipping south 60-85º. The SMC is a series of structurally controlled zones dipping southeast 25-50° with wide alteration. It is interpreted to be a Riedel Shear between the ’04 …


Geochemical Comparison Of Ancient And Modern Eolian Dune Foresets Using Principal Components Analysis, David A. Little Nov 2016

Geochemical Comparison Of Ancient And Modern Eolian Dune Foresets Using Principal Components Analysis, David A. Little

Theses and Dissertations

Geochemistry has been used to determine the provenance and diagenetic history of eolian sandstone deposits. However, the grain size, sorting, cementation, and detrital composition of eolian units can change along dune foreset laminae. The purpose of this study was to test for consistent trends of compositional change along dune foresets. Such trends could increase the quality of geochemical sampling of eolian sandstones and possibly aid in estimating the original height of ancient sand dunes. XRF data was gathered for both major and trace elements from the Pennsylvanian to Permian Weber Sandstone, Early Jurassic Navajo Sandstone, and modern Coral Pink Sand …


The Sudbury Impact Structure - New Insights Into The Origin And Emplacement Of The Basal Onaping Intrusion And The Parkin, Trill And Foy Offset Dykes Of The North Range, Denise Anders Oct 2016

The Sudbury Impact Structure - New Insights Into The Origin And Emplacement Of The Basal Onaping Intrusion And The Parkin, Trill And Foy Offset Dykes Of The North Range, Denise Anders

Electronic Thesis and Dissertation Repository

The 1.85 Ga Sudbury impact structure is considered a remnant of a multi-ring basin with an estimated original diameter of 150-200 km. The so-called “Basal Onaping Intrusion” form discontinuous sheets between the Granophyre of the Sudbury Igneous Complex (SIC) and the Sandcherry Member of the Onaping Formation and had been considered part of the complex breccia series of the Onaping Formation. Based on the investigation of core and field samples from the North Range we conclude that the Basal Onaping Intrusion, in fact, are the roof rocks of the SIC and, thus, may represent the initial bulk composition of the …


Variations In Geochemistry And Mineralogy Of Aeolian Dust Deposition To Mountains In Utah And Nevada, Usa, Dylan Binder Dastrup Oct 2016

Variations In Geochemistry And Mineralogy Of Aeolian Dust Deposition To Mountains In Utah And Nevada, Usa, Dylan Binder Dastrup

Theses and Dissertations

Major and trace metal loading to mountains in the western US depends on dust sources, intensity of storms and their availability for transport during snowmelt and runoff. Previous work has been conducted on dust production, composition, and its affect on solar radiation and timing of snow melt. This study was conducted to 1) examine temporal and spatial variability in dust chemistry; 2) evaluate form and availability of major and trace elements in dust; and 3) identify potential dust sources affecting mountains in Utah and Nevada. Spring and summertime dust was collected across northern Utah over the course of three years …


Emplacement Of The Foy, Hess And Pele Offset Dykes At The Sudbury Impact Structure, Canada, Eric A. Pilles Sep 2016

Emplacement Of The Foy, Hess And Pele Offset Dykes At The Sudbury Impact Structure, Canada, Eric A. Pilles

Electronic Thesis and Dissertation Repository

The 1.85 Ga Sudbury impact structure is the remnant of what is generally considered to have been an ~150–200 km diameter impact basin in central Ontario, Canada. The so-called Offset Dykes are impact melt dykes that are found concentrically around – and extending radially outward from – the Sudbury Igneous Complex (SIC), a ~3 km thick differentiated impact melt sheet. The dykes are typically composed of two main phases of granodiorite: an inclusion- and sulfide-rich granodiorite in the centre of the dyke, and an inclusion- and sulfide-poor granodiorite along the margins of the dyke. This study uses a combination of …


Constraining The Formation And Alteration Of Sudbury Breccia, Ontario, Canada: Implications For Footwall Cu-Ni-Pge Exploration, Jonathan W. O'Callaghan Sep 2016

Constraining The Formation And Alteration Of Sudbury Breccia, Ontario, Canada: Implications For Footwall Cu-Ni-Pge Exploration, Jonathan W. O'Callaghan

Electronic Thesis and Dissertation Repository

Sudbury breccia is an impactite situated in the footwall of the 1.85 Ga Sudbury impact structure, situated in Ontario. Developing exploration vectors towards Sudbury breccia-hosted Cu-Ni-PGE mineralization is inhibited by an insufficient understanding of the relative contributions of footwall lithologies versus impact melt. By combining whole-rock geochemistry, field observations, statistical modelling and petrography, this study has determined that Sudbury breccia is a parautochthonous shock melt, which does not require a melt sheet contribution. Furthermore, the trace metal content of the breccia is largely controlled by the assimilation of mafic footwall lithologies, the exception being breccia proximal to mineralization, where a …


Role Of Sorting On The Composition Of Siliciclastic Sediment: Implications For Interpreting Provenance After Limited Transport In An Arid Climate, Forrest Christopher Driscoll Aug 2016

Role Of Sorting On The Composition Of Siliciclastic Sediment: Implications For Interpreting Provenance After Limited Transport In An Arid Climate, Forrest Christopher Driscoll

Masters Theses

This study tested whether transport distances (< 500 m) have the capacity to shape the geochemistry of sediments across multiple grain-size populations due to sorting derived from a single source. In the Stepladder Mountains, Mojave Desert, CA, a < 1 km2 [square kilometers] watershed allows for a controlled study to understand how modern sediments acquire their composition from a single granodioritic source in an arid climate where there is no chemical weathering. Sediments are naturally sorted into distinct grain-size populations, with modes ranging from very fine sand to gravel within a single, alluvial channel. Sediment samples representative of each population were petrographically and geochemically analyzed in order to test the effectiveness of commonly used discrimination diagrams. Sediments became proportionally enriched in plagioclase and biotite and depleted in K-feldspar and quartz with decreasing grain …


Geochemical Attributes Of Hydraulically Active Fractures And Their Influence On Groundwater Quality, Amy L. Hudson Jul 2016

Geochemical Attributes Of Hydraulically Active Fractures And Their Influence On Groundwater Quality, Amy L. Hudson

Doctoral Dissertations

This study utilized discrete interval diffusion sampling of a fractured bedrock well completed in schist to investigate if a natural weathering signal can be used to identify hydraulically active fractures. The open borehole well MFS-1, is the focus of the study, which is in close proximity to the recharge zone making it ideal for testing the hypotheses of this study. The hydraulically active fractures of Well MFS-1 were identified, and the dominant mixing force of the water column of the well was determined to be thermal convection in the upper portion of the well and upward gradients. The isotopic data …


Reexamination Of Ore-Forming Processes In The Emery Mining District, Powell Co., Montana, Jarred Zimmerman Jul 2016

Reexamination Of Ore-Forming Processes In The Emery Mining District, Powell Co., Montana, Jarred Zimmerman

Graduate Theses & Non-Theses

The present investigation was undertaken in collaboration with the Montana Bureau of Mines and Geology to re-evaluate the Emery district using modern methods of ore deposit study including fluid inclusions, stable isotopes, and mineral geochemistry. Results from this thesis will be an aid in reassessing the potential of the Boulder Batholith and surrounding geologic units to host large, undiscovered precious and/or base metal deposits. The Emery (aka Zosell) district was mined from the late 1800s until the early 1950s. Mineralized quartz veins are hosted by basaltic andesite flows of the late Cretaceous Elkhorn Mountain Volcanics (EMV). Two sets of veins …


Determining Groundwater Sources And Ages Via Isotope Geochemistry In Big Sky, Montana, Thomson Connie Jul 2016

Determining Groundwater Sources And Ages Via Isotope Geochemistry In Big Sky, Montana, Thomson Connie

Graduate Theses & Non-Theses

The Big Sky ski resort area in southwestern Montana is experiencing exponential growth in both development and population. Concerns have arisen over the quantity of good-quality groundwater in the region, and whether there is a large enough reserve to support the growing demand. In light of already-documented water-level decreases, and domestic wells needing to be deepened or replaced, the Montana Department of Natural Resources and Conservation (DNRC) enlisted the Montana Bureau of Mines and Geology's Ground Water Investigation Program to perform an assessment of groundwater availability and quality in the region, and define groundwater supply sources.

The geology in the …


An Investigation Of Hydrogeologic, Stratigraphic, And Structural Controls On Acer Grandidentatum Communities In A Karst Landscape, Owl Mountain Province, Fort Hood Military Installation, Texas, Melinda S. Faulkner May 2016

An Investigation Of Hydrogeologic, Stratigraphic, And Structural Controls On Acer Grandidentatum Communities In A Karst Landscape, Owl Mountain Province, Fort Hood Military Installation, Texas, Melinda S. Faulkner

Electronic Theses and Dissertations

The Owl Mountain Province is located within the Fort Hood Military Installation, an approximately 880 km2 installation established in the 1940s in Bell and Coryell counties, Texas, which has undergone extensive land use changes associated with military training, maintaining much of the vegetation in early succession. This study investigates thelithologic, stratigraphic, and structural controls on the hydrologic, hydrogeologic, and geomorphologic evolution of the Owl Mountain Province as expressed by mesic vegetation communities, including Pleistocene relicts Acer grandidentatum, within karst terrains. These systems exhibit complexly overprinted speleogenetic evolutions within a dynamic groundwater regime resulting from regional climate shifts throughout the …


Speleogenesis Of Critchfield Bat Caves And Associated Hydrogeology Of The Northern Edwards Aquifer, Williamson County, Texas, Ashley N. Landers May 2016

Speleogenesis Of Critchfield Bat Caves And Associated Hydrogeology Of The Northern Edwards Aquifer, Williamson County, Texas, Ashley N. Landers

Electronic Theses and Dissertations

Karst development in the Edwards Aquifer has been significantly studied in the San Antonio and Barton Spring Segments; however, karst development remains poorly studied in the Northern Segment. Detailed characterization of the Northern Segment is vital for future water conservation because of increasing urban sprawl along the Interstate 35 corridor. The Northern Segment of the Edwards Aquifer consists of Lower Cretaceous strata of the Comanche Peak, Edwards, and Georgetown formations. The stratigraphy is dominated by Edwards Limestone as it is the only formation that crops out in the study area.

Karst, stratigraphic, GIS, and geochemical studies were conducted to evaluate …


Geochemical And Petrological Characterizations Of Peridotite And Related Rocks In Marquette County, Michigan, Andrew Lloyd Sasso Apr 2016

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 Apr 2016

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 …


Paragenesis And Geochemistry Of The Calvert Tungsten Skarn Deposit, Pioneer Mountains, Montana, Joshua Messenger Apr 2016

Paragenesis And Geochemistry Of The Calvert Tungsten Skarn Deposit, Pioneer Mountains, Montana, Joshua Messenger

Graduate Theses & Non-Theses

The Calvert tungsten skarn deposit is located in the northern extent of the West Pioneer Mountains, approximately 40 miles southwest of Butte, Montana. The orebody was a significant tungsten producer from 1956-1957 and 1960-1962 during which time the mine produced a total of approximately 113,000 tons of ore averaging 1.10% WO3. The mine has a measured reserve of 128,000 tons at 1.10% WO3. The scheelite-bearing deposit occurs within skarn developed in the Pennsylvanian Amsden Formation near or in contact with a satellite pluton of the Late Cretaceous Pioneer Batholith.

Mineral paragenetic studies reveal at least three …


Mineralogy And Environmental Geochemistry Of Slag In Lower Area One, Butte, Montana, Jenna Kaplan Apr 2016

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 …


Geochemical And Petrological Studies On The Origin Of Nickel-Copper Sulfide Mineralization At The Eagle Lntrusion In Marquette County, Michigan, Benjamin Davis Hinks Apr 2016

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 …


High Flow Events As Hot Moments Of Reactive Fe And P Export: Impacts Of Land Cover And Seasonality, Braden Rosenberg Jan 2016

High Flow Events As Hot Moments Of Reactive Fe And P Export: Impacts Of Land Cover And Seasonality, Braden Rosenberg

Graduate College Dissertations and Theses

High flow events often comprise the majority of annual discharge and riverine geochemical flux of phosphorus (P) and metals such as iron (Fe) and manganese (Mn) due to glacial melt, snowmelt, and storm-driven sustained high flow. Aquatic ecosystem productivity in receiving water bodies such as Lake Champlain and the Gulf of Alaska (GoA) are impacted by the riverine import of nutrients. The magnitude of these high flow events can be a strong predictor of receiving water body conditions, and in some cases can contribute to eutrophication. We explore the intersection of high flow events and land cover in contrasting catchments …


Geochemical Investigation Of Anomalous Arsenic Enrichment In The Santiago Peak Volcanics Of Southern California, Elizabeth C. Johnston Jan 2016

Geochemical Investigation Of Anomalous Arsenic Enrichment In The Santiago Peak Volcanics Of Southern California, Elizabeth C. Johnston

Theses

Arsenic (As) is enriched in the Santiago Peak Volcanics (SPV) that crop out at Black Mountain Open Space Park in San Diego, CA. Thus, the Black Mountain SPV present an excellent opportunity to investigate As enrichment in ancient volcanic arc systems as a result of deep earth subduction zone processes. Through targeted field study of this unit, we aim to (1) confirm the volcanic arc provenance of rocks cropping out at Black Mountain, (2) investigate As enrichment in relation to volcanic arc processes, and (3) propose a model for As occurrence in the SPV. Our findings indicate Black Mountain SPV …


In Situ Geochemistry Of Middle Ordovician Dolomites Of The Upper Mississippi Valley: Evaluation Of The Dorag Model And New Implications For Dolomitizing Fluids, John Michael Callen Jan 2016

In Situ Geochemistry Of Middle Ordovician Dolomites Of The Upper Mississippi Valley: Evaluation Of The Dorag Model And New Implications For Dolomitizing Fluids, John Michael Callen

LSU Master's Theses

The dolomitization and diagenetic history of Ordovician carbonates of southern Wisconsin has been studied for over a century. Previous studies attributed dolomitization to various single or multiple diagenetic factors and environments. The goal of the study was to resolve arguments regarding dolomitization models, including Badiozamani’s often cited but recently questioned mixing zone model, using LA-ICP-MS focusing on REE to determine the nature of dolomitizing fluids. Analysis revealed that particulate material incorporated into the dolomite affected the geochemical results of many of the samples. Integrating geochemical data with petrographic evidence for diagenetic history, the studied Decorah Formation dolomites were assigned to …


Rhyolite And Trachyte Formation At Lake City Caldera: Insight From Quantitative Textural And Geochemical Analyses, Jordan Lubbers Jan 2016

Rhyolite And Trachyte Formation At Lake City Caldera: Insight From Quantitative Textural And Geochemical Analyses, Jordan Lubbers

Dissertations, Master's Theses and Master's Reports

Lake City Caldera (22.93 ± 0.02 Ma) is the youngest of 15 Tertiary calderas found within the Southern Rocky Mountain Volcanic Field (SRMVF). Extreme topographical relief of the area reveals the three dimensional exposure of a complex, high-k calc-alkaline, magmatic system, which provides us with the opportunity to study, in detail, how large silicic magmas evolve in the subsurface. The Lake City igneous system is comprised of two major units: a resurgent syenite intrusion and the Sunshine Peak Tuff (Lower, Middle, and Upper). Bulk-rock analyses indicate that the Lower and Middle Sunshine Peak tuff are crystal poor and rhyolitic in …


National Evaluation For Development And Exploration Potential Of Mineral Commodities In Produced Waters, Stephanie Ray Jan 2016

National Evaluation For Development And Exploration Potential Of Mineral Commodities In Produced Waters, Stephanie Ray

Open Access Theses & Dissertations

The U.S. Geological Survey recently updated a geochemical database consisting of data for approximately 160,000 produced waters samples, primarily from petroleum and geothermal reservoirs. Using major and trace elements from conventional and unconventional well types from the database, this Thesis provides a comprehensive, national evaluation for mineral commodity potential in produced waters. Produced waters contain virtually every naturally occurring element and can range in salinity to several times that of seawater. Despite the typical outlook to view produced waters as a waste, they have potential for natural resource development.

This Thesis provides, for each mineral commodity found in the produced …


The Role Of Organic Matter In The Surface Chemistry Of Arsenic Compounds On Iron−(Oxyhydr)Oxides Studied By Atr-Ftir, Arthur Situm Jan 2016

The Role Of Organic Matter In The Surface Chemistry Of Arsenic Compounds On Iron−(Oxyhydr)Oxides Studied By Atr-Ftir, Arthur Situm

Theses and Dissertations (Comprehensive)

The interaction of organic matter with the interfaces of active soil components such as iron oxides is ubiquitous within soil environments. The presence of organics at these interfaces may have implications for other soil constituents whose mobility is controlled by their ability to bind to active soil components. Most of the studies performed to date which look at these interactions are bulk/batch studies performed ex-situ. Attenuated total internal reflectance Fourier transform infrared spectroscopy (ATR-FTIR) was utilized within this work to study interactions between select model organics (citrate, oxalate and pyrocatechol) and iron−(oxyhydr)oxides, as well as their effect on the surface …


Metamorphic Conditions Of Aluminous Gneisses In The Sawtooth Metamorphic Complex, Idaho, Usa: Implications For The Middle-Lower Crust, Eleanor Wesley-Anne Smith Jan 2016

Metamorphic Conditions Of Aluminous Gneisses In The Sawtooth Metamorphic Complex, Idaho, Usa: Implications For The Middle-Lower Crust, Eleanor Wesley-Anne Smith

LSU Master's Theses

The Sawtooth Complex (SMC) of central Idaho contains metasedimentary units that elucidate the pressure-temperature conditions and potentially, the evolution of Precambrian crust in the northwestern United States. Petrographic analysis, whole rock geochemistry, and geothermobarometry combined with thermodynamic phase equilibrium modeling record a regional metamorphic pathway for SMC aluminous gneisses characterized by burial to middle-lower crustal levels with at least two deformational events, followed by a retrograde overprint. P-T conditions are generally consistent with the peak assemblage of SMC aluminous gneisses of bt + grt + sil + ilm + zrn + mnz ± pl ± qtz ± kfs ± ap …


Avon Alkaline Igneous Province, Missouri: Characterization Of Subcontinental Mantle Source And Evolution Via Chemical Analysis Of Olivine, Zachary William Freeman Jan 2016

Avon Alkaline Igneous Province, Missouri: Characterization Of Subcontinental Mantle Source And Evolution Via Chemical Analysis Of Olivine, Zachary William Freeman

Masters Theses

"This article presents the crystallization age of, and composition of olivine phenocrysts within an alnoite of, the Avon Alkaline Igneous Province (AAIP) of Ste. Genevieve County, Missouri. The AAIP is an ultramafic igneous province consisting of approx. 80 known intrusives of diverse lithology and texture. 40Ar/39 Ar geochronology indicates an emplacement age of 386 +/- 1 Ma, which establishes the AAIP as the only known Devonian-age ultramafic igneous body in the Midwestern U.S. Study of the AAIP provides a unique opportunity to characterize the Devonian-age subcontinental mantle and the processes that generated the suite of ultramafic rocks present …


A Trace Metal Content Database Of Cave Sediments Of Midcontinent U.S.A., Matthew Dale Smith Jan 2016

A Trace Metal Content Database Of Cave Sediments Of Midcontinent U.S.A., Matthew Dale Smith

MSU Graduate Theses

The midcontinent of the United States has thousands of documented caves. These caves contain cave sediments, which are the accumulation of biological, geological, and anthropological debris. At this time there is no known database for trace metals of cave sediments of the midcontinent United States. Considering that caves host a wide variety of life, it is important to create a database to examine potential effects of trace metals on cave systems. In order to develop this baseline, 14 caves were sampled from across the midcontinent. Caves were selected based on geologic and hydrologic attributes. The sediments were analyzed for the …