Digital Commons Network^™

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

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

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

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

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

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

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

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

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

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 …