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Fluvial And Sequence Stratigraphy Analysis Of The Hell Creek And Fort Union Formations To Test Models For Sedimentation Across The Cretaceous-Paleogene Boundary In Makoshika State Park, Glendive, Montana, Quintin Bendixen May 2021

Fluvial And Sequence Stratigraphy Analysis Of The Hell Creek And Fort Union Formations To Test Models For Sedimentation Across The Cretaceous-Paleogene Boundary In Makoshika State Park, Glendive, Montana, Quintin Bendixen

Theses and Dissertations

The Cretaceous-Paleogene Boundary outcrops extensively throughout Makoshika State Park in Glendive, Montana. A distinct change in sedimentation style occurs across the Cretaceous- Paleogene in the Williston Basin deposits found in eastern Montana and western North Dakota. The well documented Hell Creek Formation of the Upper Cretaceous period consists of fresh and brackish water influenced deposits on the western low-lying coast of the Western Interior Seaway. The overlying Fort Union Formation consists of coals and fluvial sandstone deposits. Geologic explanations for the depositional shift include tectonic forces of the Sevier/Laramide Orogeny to the west, The Cretaceous-Paleogene Extinction Event, and the advancement …


Monitoring Of Carbon Dioxide Injection In The Southeastern United States, Adil Murad Awad Alshammari Apr 2021

Monitoring Of Carbon Dioxide Injection In The Southeastern United States, Adil Murad Awad Alshammari

Theses and Dissertations

Over the past few decades, measured levels of atmospheric carbon dioxide have substantially increased. One way to limit the adverse impacts of increased carbon dioxide concentrations is to capture and store it inside Earth's subsurface, a process known as CO2 sequestration. This method's success is critically dependent on the ability to confine injected CO2 for up to thousands of years. Establishing effective maintenance of sealing systems of reservoirs is of importance to prevent CO2 leakage. Understanding the nature and rate of potential CO2 leakage related to this injection process is essential to evaluating seal effectiveness and ultimately mitigating global warming. …


Carbonatite Metasomatism And Water Systematics Of Peridotite Xenoliths From Lanzarote, Canaries, Sierra N. Patterson Apr 2021

Carbonatite Metasomatism And Water Systematics Of Peridotite Xenoliths From Lanzarote, Canaries, Sierra N. Patterson

Theses and Dissertations

Water in Earth’s mantle, present as structurally bound hydrogen in minerals, influences large scale processes like mantle deformation, plate tectonics, and melting. To better understand the processes controlling water concentrations in the Earth’s upper mantle, we analyzed hydrogen (calculated as ppm wt. H2O), major, and trace element concentrations in minerals from peridotite mantle xenoliths of Lanzarote, Canaries. The Canaries Islands are thought to be the surface expression of a deep-seated mantle plume erupting through the Atlantic Ocean lithosphere. Carbonatite magmas have erupted in the Canaries and previous studies have shown evidence for carbonatite metasomatism in Lanzarote peridotites. Thus, …


Radium At The Lost City And Mid-Cayman Rise Hydrothermal Fields, Jessica D. Frankle Apr 2021

Radium At The Lost City And Mid-Cayman Rise Hydrothermal Fields, Jessica D. Frankle

Theses and Dissertations

Fluid residence times of deep-sea hydrothermal circulation influence chemical cycling in the ocean. While fluid residence time estimates exist for many basalt-hosted systems, no estimates exist for serpentinite hosted systems that emit fluids with inherently different chemistry. We measured short- and long-lived radium (Ra) nuclides in fluids from two hydrothermal systems on the Mid-Cayman Rise to constrain their residence times: the Von Damm Vent Field, a mixed ultramafic-mafic system, and the Piccard Vent Field, a mafic, neovolcanic system. Von Damm fluids contain remarkably elevated 223Ra activities (half-life = 11.4 days), surpassing those from basalt-hosted hydrothermal systems by one to two …


Analyzing Strain Localization, Kinematic Partitioning And Fluid Flow In The Pulo Do Lobo Metasedimentary Rocks Along The Southern Iberian Shear Zone, Andalucia, Spain, Nancy Alejandra Carman Dec 2020

Analyzing Strain Localization, Kinematic Partitioning And Fluid Flow In The Pulo Do Lobo Metasedimentary Rocks Along The Southern Iberian Shear Zone, Andalucia, Spain, Nancy Alejandra Carman

Theses and Dissertations

The Southern Iberian Shear Zone is a regional scale ductile shear zone that placed Beja-Acebuches metabasites over metapelite and quartzite rocks of the Pulo do Lobo Formation in a transpressional deformation with components of thrust and left-lateral movement. This project evaluates factors that contributed to strain localization at a variety of scales within the Pulo do Lobo formation, including lithologic variations, microstructures, and fluid flow. Additionally, microstructural data are used to test whether kinematic partitioning accompanied strain localization. Grain scale asymmetric indicators of sigma-type clasts, S-C fabrics, and asymmetric folds indicate dominant thrust motion. Strain intensity and metamorphic grade increase …


Surface Alteration In The Ölkelduháls, Nesjavellir, And Geysir Hydrothermal Systems, Iceland: Implications For Mars, Jordan Ludyan Dec 2020

Surface Alteration In The Ölkelduháls, Nesjavellir, And Geysir Hydrothermal Systems, Iceland: Implications For Mars, Jordan Ludyan

Theses and Dissertations

Silica- and sulfate-rich deposits observed by Mars Exploration Rover (MER) Spirit near Home Plate, Gusev crater, Mars, indicate alteration of Mars basalt by a diverse array of hydrothermal fluids and processes. Constraining the precise fluid conditions present at the time of deposition for these deposits on Mars relies on investigations of terrestrial hydrothermal systems that produce similar mineral assemblages. Alteration products and fluids collected from the Ölkelduháls, Nesjavellir, and Geysir hydrothermal areas in southern Iceland cover a wide range of end-member and intermediate fluid and alteration environments, and provide a means to compare the secondary minerals produced from different hydrothermal …


Sedimentology, Sequence Stratigraphy, And High-Precision U-Pb Age Constraints On The Late Paleozoic Ansilta Formation, Calingasta-Uspallata Basin, Nw Argentina, John Ethan Malone Dec 2020

Sedimentology, Sequence Stratigraphy, And High-Precision U-Pb Age Constraints On The Late Paleozoic Ansilta Formation, Calingasta-Uspallata Basin, Nw Argentina, John Ethan Malone

Theses and Dissertations

The Ansilta Formation, located several kilometers east of the Astronomical Observatory El Leoncito near Barreal, San Juan Province, Argentina was deposited during the late Mississippian to early Pennsylvanian. This succession includes glacimarine, nearshore, and fluvial systems deposited at the mid-Carboniferous portion of the late Paleozoic ice age within the Calingasta—Uspallata Basin on the western margin of the Protoprecordillera. The lower member of the Ansilta Formation is equivalent to the nearby Leoncito, Majaditas, and Hoyada Verde formations, and is composed of diamictite, conglomerates, sandstones, pebbly mudstones, and laminated mudstone. Glacial environments are unique in that facies changes occur as a result …


Impacts Of Land-Use Change On The Menominee River In Jo Daviess County, Illinois, Preston J. Konop Oct 2020

Impacts Of Land-Use Change On The Menominee River In Jo Daviess County, Illinois, Preston J. Konop

Theses and Dissertations

This study addresses land-use changes in Jo Daviess County, Illinois, and their effects on the Menominee River. The Menominee River flows north to south through Jo Daviess County, and southern Grant County, Wisconsin. Many of the surrounding properties are agricultural and have undergone developmental and land-use changes that may affect the flood flashiness of the Menominee River. The concern with increasing flood flashiness of the Menominee River include more frequent flooding events, undercutting of riverbanks, and increased amounts of sediment transport from upstream locations into the Mississippi River. Increases in impermeable surfaces have led to greater amounts of runoff during …


Late Paleozoic Climatic Reconstruction Of Western Argentina: Glacial Extent And Deglaciation Of Southwestern Gondwana, Kathryn N. Pauls Aug 2020

Late Paleozoic Climatic Reconstruction Of Western Argentina: Glacial Extent And Deglaciation Of Southwestern Gondwana, Kathryn N. Pauls

Theses and Dissertations

Throughout its history Earth has experienced both icehouse and greenhouse conditions. Shifts and transitions from one end member to the other are driven by numerous driving mechanisms on global, orbital and more local scales. In particular, the late Paleozoic ice age (LPIA) is thought to have been driven by global drivers such as the drift of the Gondwanan continent across the South Pole, fluctuations in atmospheric CO2 concentrations, and Milankovitch cycles. It was also affected by more local and regional drivers such as active tectonism along accretionary margins and changes in atmospheric and oceanic circulation patterns. South American Gondwana provides …


Water Chemistry And Lake Dynamics Of Laguna Bacalar, Quintana Roo, Mexico, Ryan Matzuk Aug 2020

Water Chemistry And Lake Dynamics Of Laguna Bacalar, Quintana Roo, Mexico, Ryan Matzuk

Theses and Dissertations

Laguna Bacalar in the Quintana Roo region is the second largest lake in Mexico and contains freshwater derived solely from groundwater. Local geology on the Yucatan Peninsula is karstic and the southern shoreline of Laguna Bacalar is spotted with a handful of cenotes that contribute substantial amounts of inflowing groundwater to the lake. This is shown by sonde profile data taken in one of the largest cenotes in the area. Outflow is dominated by a surface water outlet in the southern portion of the lake and an unknown amount of outflowing groundwater. During January of 2017 through 2019, UWM researchers …


Characterization Of Water Pathways And Hydrolytic Weakening Within Naturally Deformed Quartz Grains Along The Willard Thrust Fault, Utah, Charles Alexander Martin May 2020

Characterization Of Water Pathways And Hydrolytic Weakening Within Naturally Deformed Quartz Grains Along The Willard Thrust Fault, Utah, Charles Alexander Martin

Theses and Dissertations

Evidence of water infiltration was examined in naturally deformed quartzite clasts from diamictite of the Mineral Fork Formation sampled from Antelope Island in the Great Salt Lake, Utah. The diamictite deformed via subsimple shear in the footwall of the Willard thrust fault and displays spatial variations in strain intensity. Evidence of water infiltration was investigated utilizing three complimentary techniques: standard petrographic microscopy to identify microstructures and interpret deformation mechanisms; scanning electron microscopy cathodoluminescence (SEM-CL) to create maps of healed microfractures and subgrain boundaries related to pathways of fluid infiltration; and synchrotron-source Fourier-transform infrared spectroscopy (FTIR) to create micron-scale water absorbance …


Simulating The Effects Of Urbanization And Climate Change On Ground Water Recharging Using The Usgs Precipitation And Runoff Modelling System (Prms), Kenneth Oanes May 2020

Simulating The Effects Of Urbanization And Climate Change On Ground Water Recharging Using The Usgs Precipitation And Runoff Modelling System (Prms), Kenneth Oanes

Theses and Dissertations

The Root River watershed, located in southeastern Wisconsin, was selected to be the subject of a study modeling the impacts of urbanization and climate change on groundwater recharge. Historical and projected (2035) land use data for the study area was sourced from the Southeast Wisconsin Regional Planning Committee (SEWRPC). The USGS Precipitation and Runoff Modelling System (PRMS) was selected to estimate recharge from a 35-year period of historical climate data (1980-2014). PRMS was run for the full 35-year time period under each land-use scenario and model outputs for evapotranspiration (ET), runoff, and recharge were calculated on a daily time-step.

Model …


A Feasibility Study Of Microbialites As Paleomagnetic Recorders, Ji-In Jung May 2020

A Feasibility Study Of Microbialites As Paleomagnetic Recorders, Ji-In Jung

Theses and Dissertations

Microbialites are carbonate organosedimentary deposits formed by benthic microbial communities that trap and bind detrital sediments, and/or inorganic and biologically influenced calcification. Any ferromagnetic particles incorporated into the microbialite structure have the potential to preserve variations in Earth’s magnetic field. A paleomagnetic record in microbialites would be useful for reconstructing the geomagnetic field because it may record at a high temporal resolution based on estimated growth rates, thus preserving relatively short-period variations of the Earth’s magnetic field. In addition, microbialites can be found in the geologic record going back ~3.5 Ga, hence potentially providing information on very ancient variations in …


The Role Of Floating Gardens To Alter The Water Quality Of The Chicago River: Chicago, Il, Emmett Andrew Spooner Mar 2020

The Role Of Floating Gardens To Alter The Water Quality Of The Chicago River: Chicago, Il, Emmett Andrew Spooner

Theses and Dissertations

The pollution of heavy metals within surface water is a rising global concern. As heavy metals are transported through rivers, they can bioaccumulate through the food web, leading to harmful concentrations within waterways. In urban areas such as the city of Chicago, Illinois, the use of road salts is a concern as elevated concentrations of chloride (Cl–) can reduce surface water quality. Since surface waters can carry heavy metals and Cl– salts over a large distance, methods of in-situ phytoremediation are of growing importance. Through a pilot project, a floating garden system has been installed along a portion of the …


The Dynamics And Speciation Of Arsenic In Drinking Water Wells In Eastern Wisconsin, Evvan Plank Dec 2019

The Dynamics And Speciation Of Arsenic In Drinking Water Wells In Eastern Wisconsin, Evvan Plank

Theses and Dissertations

Arsenic typically develops in Eastern Wisconsin groundwater as a result of oxidation of sulfide bearing minerals in the limestone bedrock (Schreiber et al. 2000). Naturally occurring arsenic exists in groundwater as oxyanions which have two oxidation states, As(III) and As(V). Under ambient pH conditions As(V) is primarily present as an anion (i.e., H2AsO4-) while As(III) tends to be uncharged (i.e., H3AsO3), making it much more difficult to remove through the existing treatment techniques such as adsorption and reverse osmosis (RO). Although many studies exist establishing arsenic concentrations across Wisconsin, there is a lack of investigations into the concentrations of each …


Sedimentological And Geochemical Analysis Of Deep-Water Deposits In The Mojón De Hierro Formation At Arroyo Garrido, Tepuel-Genoa Basin, Patagonia, Argentina, Natalie Beatrice Mcnall Aug 2019

Sedimentological And Geochemical Analysis Of Deep-Water Deposits In The Mojón De Hierro Formation At Arroyo Garrido, Tepuel-Genoa Basin, Patagonia, Argentina, Natalie Beatrice Mcnall

Theses and Dissertations

The Earth has had multiple Phanerozoic glacial intervals but the Late Paleozoic Ice Age (LPIA) was its longest and most extensive, lasting from the Late Devonian (~372 Ma) until the Late Permian (~254 Ma). The LPIA is the last complete climate shift from a greenhouse to icehouse and back to a greenhouse state and the only one to occur on a biologically complex Earth. Therefore, it provides perspectives on deep-time climatic transitions, the parameters controlling them, and the Earth’s physical, chemical and biological responses to such climate changes. Research on mid to high-latitude deposits in Gondwana provides evidence that the …


Mantle Heterogeneity From The Mantle Plume Perspective: Sources Vs. Processes, Paul Béguelin Jul 2019

Mantle Heterogeneity From The Mantle Plume Perspective: Sources Vs. Processes, Paul Béguelin

Theses and Dissertations

Oceanic island basalts (OIB) which are derived from mantle plumes sample a compositionally heterogeneous mantle, as revealed by their radiogenic isotope systematics. Isotope compositions recurring in distinct hotspots have been used to characterize the composition and heterogeneity of the mantle as well as the thermochemical structure of upwelling plumes, with the assumption that the isotope composition of erupted lavas directly reflects that of their mantle source.

Here I test how source transport, melting and hybridization in the upper mantle through space and time control the expression of deep mantle sources in erupted lavas. This work is focused on the Azores …


Glacial-Interglacial Changes In The Thermocline Structure Of The Makassar Strait: Implications For Changes In The Indonesian Throughflow, Michael Lis Jul 2019

Glacial-Interglacial Changes In The Thermocline Structure Of The Makassar Strait: Implications For Changes In The Indonesian Throughflow, Michael Lis

Theses and Dissertations

The Indo-Pacific Warm Pool exerts a strong influence on the global climate system because it partially controls heat and moisture exchange (pressure gradient) between the atmosphere and ocean, and thus, the intensity of the Indonesian throughflow (ITF) via the Makassar Strait, the main passage of water connecting the Pacific and Indian Oceans. The magnitude of ITF is reflected by the structure of the oceanic thermocline. Here, we use shell δ18O signatures and trace element composition of foraminifera (Globigerinoides ruber, Pulleniatina obliquiloculata, and Globigerinoides menardii) in two sediment records spanning the past 30 kya collected from …


3-D Potential Field Inversion Camp Clubhouse Crossroads Mafic Intrusive Pluton, Coastal Plain, South Carolina, Kubra Sibel Albayrak Jul 2019

3-D Potential Field Inversion Camp Clubhouse Crossroads Mafic Intrusive Pluton, Coastal Plain, South Carolina, Kubra Sibel Albayrak

Theses and Dissertations

The Central Atlantic Magmatic Province (CAMP) at the Triassic-Jurassic boundary, is the largest known igneous province in the world. However, the geometry and volume of CAMP intrusives under the Coastal Plain of the southeastern United States are poorly known. Under the Coastal Plain sediments of Georgia and South Carolina, the “J” seismic reflector was predicted to be produced by a CAMP lava flow. Recent studies of seismic and well data have shown that the “J” reflector is an unconformity and only locally a CAMP lava flow. In the Clubhouse Crossroads area of South Carolina, seismic reflection, seismic refraction, and well …


Fluvial Architecture And Reservoir Modeling Along The Strike Direction Of The Trail Member Of The Ericson Sandstone, Mesaverde Group In Southwest Wyoming, April Anahi Trevino Jul 2019

Fluvial Architecture And Reservoir Modeling Along The Strike Direction Of The Trail Member Of The Ericson Sandstone, Mesaverde Group In Southwest Wyoming, April Anahi Trevino

Theses and Dissertations

The Trail Member of the upper Cretaceous Ericson Sandstone, part of the Mesaverde Group, is exposed along hundreds of square kilometers through Wyoming along the flanks of several Laramide structural uplifts. This presents a unique opportunity to study the detailed architecture based on bed-scale heterogeneity and better assess the reservoir potential of these strata in outcrop exposure on a regional-scale, and to then relate these observations to producing fields nearby. The fluvial-dominated Trail Member formed as sediments traveled from the active Sevier thrust belt to the Cretaceous Interior Seaway, forming a basinward progradational clastic wedge along a relatively high gradient. …


Nature And Origin Of Fissure Ore At The Porphyry-Epithermal Transition Zone Of The Bingham Canyon Porphyry Cu-Au-Mo Deposit, Utah, David Harris Tomlinson Jul 2019

Nature And Origin Of Fissure Ore At The Porphyry-Epithermal Transition Zone Of The Bingham Canyon Porphyry Cu-Au-Mo Deposit, Utah, David Harris Tomlinson

Theses and Dissertations

Late-stage fissure-filling ore at the world class Bingham Canyon, Utah, porphyry copper deposit has long been recognized, but poorly studied. Physical and chemical characterization of the Pb-Zn-Cu-Ag-Au mineralized fissures in the porphyry-epithermal transition zone provides insight into the origin, timing, and controls of ore deposition. These sheared sulfide-rich fissures are dominated by pyrite and multiple generations of quartz, with lesser amounts of other sulfides and gangue minerals. Au (0.27 to 4.61 ppm) provides the most value to the ore in the transition zone. Host rocks include Eocene monzonite and Paleozoic limestone and quartzite"”all of which can contain economic ore bodies. …


Multi-Stage Construction Of The Little Cottonwood Stock, Utah: Origin, Intrusion, Venting,Mineralization, And Mass Movement, Collin G. Jensen Jul 2019

Multi-Stage Construction Of The Little Cottonwood Stock, Utah: Origin, Intrusion, Venting,Mineralization, And Mass Movement, Collin G. Jensen

Theses and Dissertations

The Little Cottonwood stock in central Utah, USA, is a composite granitic pluton that hosts the White Pine porphyry Mo-W deposit towards its northeast margin. The deposit is centered on the smaller White Pine intrusion, and associated igneous units include the Red Pine porphyry, phreatomagmatic pebble dikes, and rhyolite dikes. Twelve new U-Pb zircon LA-ICP-MS ages, for samples from this deposit and in pebble dikes from the nearby East Traverse Mountains, give peak ages of about 30 Ma and 27 Ma for the Little Cottonwood stock and White Pine intrusion, respectively, which correlate well with ages from previous studies. Ages …


Basinward Trends In Fluvial Architecture, Connectivity, And Reservoir Characterization Of The Trail Member, Ericson Sandstone, Mesaverde Group In Wyoming, Utah, And Colorado, Usa, Chelsea Anne Jolley Jun 2019

Basinward Trends In Fluvial Architecture, Connectivity, And Reservoir Characterization Of The Trail Member, Ericson Sandstone, Mesaverde Group In Wyoming, Utah, And Colorado, Usa, Chelsea Anne Jolley

Theses and Dissertations

The Late Cretaceous Trail Member of the Ericson Sandstone represents a regionally extensive fluvial system that transported sediments from the Sevier fold and thrust belt and Uinta Mountain uplift to the Western Interior Seaway. The Trail Member is a petroleum reservoir target that has unpredictable production rates due to the unknown behavior and connectivity of channel sandstones. The abundant outcrop, wellbore, and core data available allows for a comprehensive analysis of how the fluvial architecture, connectivity, and reservoir quality change along 65 km of depositional dip. Observations made at Flaming Gorge and Clay Basin (most landward field locations) suggest a …


Testing The Late Paleozoic Ice Volume Paradox In The Southernmost Paraná Basin, Brazil, Nicholas David Fedorchuk May 2019

Testing The Late Paleozoic Ice Volume Paradox In The Southernmost Paraná Basin, Brazil, Nicholas David Fedorchuk

Theses and Dissertations

The late Paleozoic ice age (LPIA; ~372-259 Ma) was the last complete transition from icehouse to greenhouse conditions on a fully vegetated Earth, making it a relevant analog for modern Earth systems. High frequency glacioeustatic fluctuation of ~100-200 m during the late Paleozoic are described by some authors in low paleolatitude basins and attributed to the orbitally-driven, waxing and waning of a massive (~20-35 x 106 km2) hypothetical ice sheet. This massive ice sheet is traditionally interpreted to have covered much of southern Gondwana for >100 m.y. Meanwhile, recent studies of high-paleolatitude glacial deposits imply a much more complex pattern …


Anthropogenically Driven Changes To Shallow Groundwater In Southeastern Wisconsin And Its Effects On The Aquifer Microbial Communities, Madeline Jean Salo May 2019

Anthropogenically Driven Changes To Shallow Groundwater In Southeastern Wisconsin And Its Effects On The Aquifer Microbial Communities, Madeline Jean Salo

Theses and Dissertations

This study investigates if, and to what extent, the microbial community present in the shallow groundwater of southeastern Wisconsin is affected by the influx of treated municipal wastewater effluent. The primary study area consisted of three wells located in the shallow sand and gravel aquifer along the upper Fox River in Waukesha, Wisconsin. One well is located roughly 1500 feet from the river and pumps pristine groundwater. Two riverbank inducement wells are located within 200 feet of the river and pump a mixture of groundwater and river water that contains effluent from three upstream wastewater treatment plants. Water from all …


Incorporation, Morphology, And Extinction Of Framework-Building Metazoans In Early Cambrian Reef Ecosystems From The Western Usa And Mongolia And Their Effects On Reef Diversity, David Russell Cordie May 2019

Incorporation, Morphology, And Extinction Of Framework-Building Metazoans In Early Cambrian Reef Ecosystems From The Western Usa And Mongolia And Their Effects On Reef Diversity, David Russell Cordie

Theses and Dissertations

The early Cambrian represents an important transition in the evolution of life, perhaps most vividly exemplified by reef ecosystems as they changed from microbial-supported to metazoan-supported framework reefs. Microbial reefs were initially composed of Renalcis- and Epiphyton-group calcifying microbes. Subsequent reefs began to incorporate archaeocyathan sponges within this framework. This represents a shift in the source of carbonate production, which can be quantified using thin section point counts. In archaeocyathan reefs from the western USA, carbonate contribution from metazoan framework builders increased from zero to 29.7%. Similar reefs from Mongolia increased from zero to 5.0%. Increases in Laurentian archaeocyath contributions …


Anthropogenically Driven Changes To Shallow Groundwater In Southeastern Wisconsin And Its Effects On The Aquifer Microbial Communities, Madeline Jean Salo May 2019

Anthropogenically Driven Changes To Shallow Groundwater In Southeastern Wisconsin And Its Effects On The Aquifer Microbial Communities, Madeline Jean Salo

Theses and Dissertations

This study investigates if, and to what extent, the microbial community present in the shallow groundwater of southeastern Wisconsin is affected by the influx of treated municipal wastewater effluent. The primary study area consisted of three wells located in the shallow sand and gravel aquifer along the upper Fox River in Waukesha, Wisconsin. One well is located roughly 1500 feet from the river and pumps pristine groundwater. Two riverbank inducement wells are located within 200 feet of the river and pump a mixture of groundwater and river water that contains effluent from three upstream wastewater treatment plants. Water from all …


Hydrogeologic Characteristics And Groundwater Sustainability Of A Deep Bedrock Aquifer System In Illinois, Luis Martinez Apr 2019

Hydrogeologic Characteristics And Groundwater Sustainability Of A Deep Bedrock Aquifer System In Illinois, Luis Martinez

Theses and Dissertations

Population growth and climate change has made groundwater an increasingly important freshwater resource. This study uses MODFLOW to estimate sustainable yield of a deep St. Peter Aquifer in Bloomington, IL. The city of Bloomington has installed two high capacity wells into the St. Peter Sandstone to meet its growing water demands. The St. Peter Aquifer is confined, receiving almost no modern recharge and is experiencing overexploitation in parts of Northern Illinois. I hypothesize that existing fast depletion of the deep St. Peter occurs due to lower-than-expected aquifer parameters of the aquifer. Further, current pumping of groundwater from the St. Peter, …


Water Systematics Of Samoan Peridotite Xenoliths, Aaron Wolfgang Ashley Apr 2019

Water Systematics Of Samoan Peridotite Xenoliths, Aaron Wolfgang Ashley

Theses and Dissertations

Water influences geodynamic processes such as melting, deformation and rheology. Yet its distribution in the oceanic upper mantle is primarily known indirectly from melt inclusions and glasses of erupted mantle melts (i.e. MORB and OIB). To constrain the mechanisms influencing the distribution of water in the mantle, we analyzed 15 peridotite xenoliths from Savaiʻi and 2 dunite xenoliths from Taʻū (Samoa) for water concentrations (by polarized FTIR) and major/trace elements. Savaiʻi peridotites are among the most melt depleted oceanic xenoliths recovered (degrees of melt depletion ≥15%). They show strong evidence of transient metasomatism by both carbonatite and silicate melts, with …


Endolithic Microbial Carbon Cycling In East Antarctica, Natalie Tyler Apr 2019

Endolithic Microbial Carbon Cycling In East Antarctica, Natalie Tyler

Theses and Dissertations

Microbes adapt to inhospitable conditions by colonizing niches that protect them from severe environmental conditions, making them model organisms in the search for life on other planets. Endoliths are globally ubiquitous microbes that colonize structural cavities within rocks, which protect them from environmental stressors while maintaining access to nutrition and light sources. Despite harsh katabatic winds, extreme temperature fluctuations, harmful UV radiation and exposure to desiccation, endolithic communities have been observed in Antarctica. Previous studies have found viable and abundant microbial biomass through microscopy and the addition of isotopic labels. However, due to the slow metabolic activity of these microbes, …