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Metamorphism Of Cretaceous Standstones By Natural Coal-Fires, San Rafael Swell, Utah, Alexa R. Zilberfarb 2014 Scripps College

Metamorphism Of Cretaceous Standstones By Natural Coal-Fires, San Rafael Swell, Utah, Alexa R. Zilberfarb

Scripps Senior Theses

Underground coal fires commonly metamorphose or melt surrounding rocks at temperatures exceeding 1000°C. Numerous “baked” sandstone clinker deposits occur in the Cretaceous sedimentary rocks exposed in the San Rafael Swell, UT. This study examines clinker in three main localities: 1) East Carbon, UT, 2) Helper, UT, and 3) Emery, UT. The extent of pyrometamorphism in these areas is variably developed, but reached high enough temperature in Helper, UT to initiate melting and the production of paralavas. These paralavas were examined compositionally and mineralogically to determine melting conditions, peak temperatures, and mobility of different metals as a result of pyrometamorphism. X-ray …


The Fluvial Sequence Of A Latest Changhsingian, Pre-Pt Extinction River Complex, Eastern Cape Province, South Africa, Tara Chizinski 2014 Colby College

The Fluvial Sequence Of A Latest Changhsingian, Pre-Pt Extinction River Complex, Eastern Cape Province, South Africa, Tara Chizinski

Honors Theses

The Permian–Triassic mass extinction, dated between 251.941 ± 0.037 and 251.880 ± 0.0371 Ma, is well documented in the marine record, but details of the event on land are still ambiguous and widely debated within the scientific community. This project focuses on the stratigraphic record leading up to the PT boundary at one of the critical sections in the Karoo Basin of South Africa, Wapadsberg Pass. A transition in river styles is reported to have occurred across the landscape from meandering Permian sandstone-dominated channels to Triassic braided complexes. This transition can be recorded by architectural elements, which reflect sensitive variations …


Deformation Mechanisms In The Metasedimentary Rocks Within The Kellyland Fault Zone, Washington County, Maine, Morgan E. Monz 2014 Colby College

Deformation Mechanisms In The Metasedimentary Rocks Within The Kellyland Fault Zone, Washington County, Maine, Morgan E. Monz

Honors Theses

This study focuses on a high-strain, strike-slip shear zone that juxtaposed metasedimentary rocks and a homogenous granite near the brittle-ductile transition, at a depth of 15-20 km. The metasedimentary rocks of the Flume Ridge Formation (FRF) exhibit a progressive deformation gradient of phase mixing and increasing fabric intensity across strike, northwest-to-southeast, approaching the center of the shear zone. Deformation mechanisms were controlled by metasomatic reactions in a fluid-rich fault zone. During deformation, biotite and potassium feldspar in the metasedimentary rocks reacted to form phengite—a much weaker phase. The nucleation and growth of weak phases, combined with phase mixing, decreased the …


Depositional Environment Of The St. Mary River Formation In Western Montana, Stacia M. Martineau 2014 University of Montana - Missoula

Depositional Environment Of The St. Mary River Formation In Western Montana, Stacia M. Martineau

Undergraduate Theses, Professional Papers, and Capstone Artifacts

In May 2013, the Two Medicine Dinosaur Center (TMDC) began excavation on a dinosaur bonebed in the St. Mary River Formation on Carey Butte, Montana. Since excavation started, four additional bonebeds have been discovered in the surrounding area. They display different depositional environments; two are in sandstone and the other three are in siltstone. The purpose of this study is to provide a depositional setting for the area that links all five sites together comprehensively by examining the sedimentology of the area. A stratigraphic analysis of the St. Mary River Formation of Carey Butte revealed four distinct facies associations. Facies …


Aqueous And Non-Aqueous Soil Processes On The Northern Plains Of Mars: Insights From The Distribution Of Perchlorate Salts At The Phoenix Landing Site And In Earth Analog Environments, Selby Hearth 2014 Bryn Mawr College

Aqueous And Non-Aqueous Soil Processes On The Northern Plains Of Mars: Insights From The Distribution Of Perchlorate Salts At The Phoenix Landing Site And In Earth Analog Environments, Selby Hearth

Geology Faculty Research and Scholarship

No abstract provided.


Science And Public Policy Of Earthquake Hazard Mitigation In The New Madrid Seismic Zone, Alice M. Orton 2014 University of Kentucky

Science And Public Policy Of Earthquake Hazard Mitigation In The New Madrid Seismic Zone, Alice M. Orton

Theses and Dissertations--Earth and Environmental Sciences

In the central United States, undefined earthquake sources, long earthquake recurrence intervals and uncertain ground motion attenuation models have contributed to an overstatement of regional seismic hazard for the New Madrid Seismic Zone on the National Seismic Hazard Maps. This study examined concerns regarding scientific uncertainties, overly stringent seismic mitigation policies and depressed local economy in western Kentucky through a series of informal interviews with local businessmen, public officials, and other professionals in occupations associated with seismic mitigation. Scientific and relative economic analyses were then performed using scenario earthquake models developed with FEMA’s Hazus-MH software. Effects of the 2008 Wenchuan …


Emplacement Of Pleistocene Basalt Flows Near Mccoy, Colorado, Andrea Bowen 2014 University of Mississippi

Emplacement Of Pleistocene Basalt Flows Near Mccoy, Colorado, Andrea Bowen

Electronic Theses and Dissertations

No abstract provided.


Deformation Mechanisms In Mylonites At Fletcher Peak, Washington County, Me, Ariana S. Boyd 2014 Colby College

Deformation Mechanisms In Mylonites At Fletcher Peak, Washington County, Me, Ariana S. Boyd

Honors Theses

Mylonite formation and development is dependent on a number of factors including temperature, strain rate, and fluid fugacity. All three factors affect flow stress and viscosity; thus, a variance in each will affect the development of mylonites. This study focuses on factors leading to the formation of mylonite surrounded by ultramylonite of the same protolith, along-strike to one another at the center of a fault zone. The rocks in question are from the Deblois granite cut by the Kellyland fault zone, a ductile strike-slip fault zone within the larger Norumbega fault system in eastern Maine. The Deblois granite as a …


Fluctuations In Resistivity In The Tuscaloosa Marine Shale, Southwest Mississippi And Southeast Louisiana, Thomas Hetherington Story 2014 University of Mississippi

Fluctuations In Resistivity In The Tuscaloosa Marine Shale, Southwest Mississippi And Southeast Louisiana, Thomas Hetherington Story

Electronic Theses and Dissertations

The Tuscaloosa Marine Shale in southwest Mississippi and Southeast Louisiana's Florida Parishes has become an unconventional target for the exploration and production of oil. Spurred by early estimates of over 7 billion barrels of oil in place, the target region for this production is the basal portion of the shale where a continuous increase in resistivity greater than 5 Ohmm can be observed. This increase was originally attributed solely to the generation of hydrocarbons from the organic matter contained within the shale, with the presence of the oil and gas impeding the flow of electrons through what would normally be …


From Marsquakes To Terraforming: The Role Of Planetary Geology In Science Fiction Literature, Katherine Shover 14 2014 DePauw University

From Marsquakes To Terraforming: The Role Of Planetary Geology In Science Fiction Literature, Katherine Shover 14

Honor Scholar Theses

None


Radon Loss From Zircon: Effects Of Microstructure On Radon Emanation And Diffusion, Marty Eakin 2014 Wayne State University

Radon Loss From Zircon: Effects Of Microstructure On Radon Emanation And Diffusion, Marty Eakin

Wayne State University Theses

Radon emanation from rocks and minerals is ubiquitous, but the mechanisms of radon loss are not well understood. Quantification of radon emanation rates from zircon has potential bearing on the reliability of U-Pb ages of zircon bearing rocks. The 238U decay chain includes 222Rn, a noble gas, which has a half-life of 3.82 days and can escape from the crystal structure of zircon if sufficient pathways exist, or by recoil if the parent 238U was very near the outer edge of the crystal. Loss of 222Rn ultimately leads to a deficiency of 206Pb, resulting in discordance between 238U-206Pb, 235U-207Pb, and …


Evaluating Spatial Outliers And Integrating Temporal Data In Air Pollution Models For The Detroit-Windsor Airshed, Brendan Francis O'leary 2014 Wayne State University

Evaluating Spatial Outliers And Integrating Temporal Data In Air Pollution Models For The Detroit-Windsor Airshed, Brendan Francis O'Leary

Wayne State University Theses

The heterogeneous nature of urban air complicates human exposure estimates and creates a need for accurate, highly detailed spatiotemporal air contaminant models. The study expands on previous investigations by the Geospatial Determinants of Health Outcomes Consortium that examined relationships between air pollutant distributions and asthma exacerbations. Two approaches, the removal of spatial data outliers and the integration of spatial and temporal data, were used to refine air quality models in the Detroit and Windsor international airshed. The evaluation of associations between the resulting air quality models and asthma exacerbations in Detroit and Windsor revealed weaker correlations with spatial outliers removed …


Investigating The Anisotropy Of Magnetic Susceptibility And Other Rock Magnetic Properties Of The Beaver River Diabase In Northeastern Minnesota, Samer H. Hariri 2014 Wayne State University

Investigating The Anisotropy Of Magnetic Susceptibility And Other Rock Magnetic Properties Of The Beaver River Diabase In Northeastern Minnesota, Samer H. Hariri

Wayne State University Theses

The Beaver River Diabase (BRD) is a series of mafic dikes and sills within the Beaver Bay Complex (BBC) of northern Minnesota, which formed during the development of the ~1.1 Ga Midcontinent Rift (MCR). The BRD is one of the youngest and most extensive intrusive phases of the BBC. The BRD dikes and sills were emplaced into the medial levels of the 6-10 kilometer-thick North Shore Volcanic Group and occur over an arcuate area extending 120 by 20 kilometers. The BRD is composed of fine- to medium-grained ophitic olivine gabbro and does not display obvious foliation or lineation features and …


Shallow Groundwater Monitoring Associated With The Deep Saline Reservoir Co2 Storage Test In Hancock County, Kentucky, E. Glynn Beck 2014 University of Kentucky

Shallow Groundwater Monitoring Associated With The Deep Saline Reservoir Co2 Storage Test In Hancock County, Kentucky, E. Glynn Beck

Report of Investigations--KGS

A carbon dioxide injection test well was drilled in 2009 to a depth of 8,126 ft below ground surface in Hancock County, Kentucky. Six hundred ninety tons of CO2 was successfully injected into Knox Group saline aquifers. Two domestic wells (MB and GB) and two domestic springs (CA and RC) were sampled to monitor any potential changes in groundwater quality associated with possible migration of CO2 from deeper saline aquifers into shallow freshwater aquifers. The four sites were sampled for pH, bicarbonate, total dissolved solids, turbidity, anions, total dissolved metals, dissolved inorganic carbon, total CO2, and …


Using Time-Lapse Three Dimensional Vertical Seismic Profiling To Monitor Injected Fluids During Geologic Carbon Sequestration, John B. Hickman 2014 University of Kentucky

Using Time-Lapse Three Dimensional Vertical Seismic Profiling To Monitor Injected Fluids During Geologic Carbon Sequestration, John B. Hickman

Report of Investigations--KGS

Two three-dimensional vertical seismic profiles (3D-VSP) were acquired at the KGS Marvin Blan No. 1 CO2 sequestration research well outside of Cloverport in Hancock County, Ky. The initial (preinjection) survey was performed September 15-16, 2010, and was followed by the injection of 361.2 metric tons of supercritical CO2 and then 584 m3 of 2 percent potassium chloride water (to displace the remaining CO2 in the wellbore) on September 22, 2010. After injection, the well was shut in with a downhole pressure of 17.5 MPa at the injected reservoir depth of 1,545.3 m. A second 3D-VSP was …


Landscape Evolution And Preservation Of Ice Over One Million Years Old Quantified With Cosmogenic Nuclides 26al, 10be, And 21ne, Ong Valley, Antarctica, Theodore C. Bibby 2014 University of North Dakota

Landscape Evolution And Preservation Of Ice Over One Million Years Old Quantified With Cosmogenic Nuclides 26al, 10be, And 21ne, Ong Valley, Antarctica, Theodore C. Bibby

Theses and Dissertations

Antarctica has been glaciated for the past 35-40 million years (Denton et al., 1991) and evidence of periodic fluctuations of the Antarctic ice sheet (AIS) during the Cenozoic are recorded in the ice sheet itself, deep sea sediments, and glacial deposits on the continent (Ingólfsson, 2004). Quaternary continental records of AIS extent is limited to few locations along the Transantarctic Mountains (TAM) and coastal continental boundaries (Denton et al., 1984; Denton et al., 1989). Records of atmospheric variation over time, glacial extents, and ice sheet responses to environmental changes are required to understand modern day forces on climate and the …


Geotechnical Engineering: Optimum Moisture Content For Compaction Of In Situ Soil At A Residential Construction Site On Five Mile Prairie, Wa., Natasha Garland Clark, Carly Sorensen, Camie Bearup 2014 Eastern Washington University

Geotechnical Engineering: Optimum Moisture Content For Compaction Of In Situ Soil At A Residential Construction Site On Five Mile Prairie, Wa., Natasha Garland Clark, Carly Sorensen, Camie Bearup

2014 Symposium

The residential construction site is located at 9117 Scarlet Sky Drive on the southwest margin of Five Mile Prairie, WA. The footprint of the proposed structure overlaps two soils. Near the road is fill material brought in to form the extended roadbed. Further from the access road is the extant soil that formed in place on the prairie. This site is approximately 2,400 feet in elevation, atop basalt. Over time loess and the Glacial Lake Missoula floods shaped the landscape. Grassy, small rolling hills cover the in-situ soil. There is a natural drainage basin below the site that features basalt …


Characterization, Diagenesis, And Geocellular Modeling Of Winnipegosis Formation Pinnacle Reefs In The Williston Basin, North Dakota, Nicholas W. Bosshart 2014 University of North Dakota

Characterization, Diagenesis, And Geocellular Modeling Of Winnipegosis Formation Pinnacle Reefs In The Williston Basin, North Dakota, Nicholas W. Bosshart

Theses and Dissertations

The Middle Devonian Winnipegosis Formation of the North Dakota Williston Basin contains pinnacle reef structures which have been targeted in the past for hydrocarbon production. These reefs have not been proven to hold economically important primary recoverable reserves, and are now being analyzed for potential CO₂ EOR and storage applications.

During this study multiple sizes of Winnipegosis Formation pinnacle reef geocellular models were constructed utilizing data from North Dakota Winnipegosis pinnacle reefs wells, cores, and thin sections. These models were then simulated for CO₂ injectivity.

Initial results show that Winnipegosis pinnacle reefs smaller than 1.5 miles in diameter are likely …


Quantifying Nutrient Cycling And Fate Within An Abandoned Feedlot And Adjacent Wetlands, Prosper Prosper Gbolo 2014 University of North Dakota

Quantifying Nutrient Cycling And Fate Within An Abandoned Feedlot And Adjacent Wetlands, Prosper Prosper Gbolo

Theses and Dissertations

Feedlot operations over the years have increased revenue and boosted economies of states and countries, but these operations have resulted in elevated concentrations of nutrients in soils, surface water, and groundwater. Feedlot operations generate large quantities of manure and other waste, which when not managed properly can result in environmental problems.

It is hypothesized that nitrogen can cause a short-term contamination of soils and groundwater beneath abandoned feedlots, but phosphorus can cause both short- and long term contamination, especially in well-drained carbonate and iron-rich soils associated with Concentrated Animal Feeding Operations. It is also hypothesized that a spectral vegetation index …


Electron Donor Contributions To Denitrification In The Elk Valley Aquifer, North Dakota, Amanda M. Krieger 2014 University of North Dakota

Electron Donor Contributions To Denitrification In The Elk Valley Aquifer, North Dakota, Amanda M. Krieger

Theses and Dissertations

Six denitrification tracer tests were performed over eight and a half years in in situ mesocosms (ISMs) in the Elk Valley Aquifer (EVA) in east-central North Dakota. Groundwater samples were analyzed to determine how much nitrate was lost beyond that explained by dilution of the bromide tracer. Additional losses were attributed to denitrification. The denitrification rates varied from 0.10 to 0.23 mg N/L/day for the six tests. In general, the major electron donors for denitrification are organic carbon (OC), pyrite (FeS2), and ferrous iron silicate minerals. In the EVA tracer tests, increases in sulfate indicated that the oxidation of pyrite …


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