Geology Commons^™

Tectonics Of The South Georgia Rift, David Michael Heffner

Theses and Dissertations

Triassic rifting of the supercontinent Pangea left behind numerous basins on what is now the eastern North American margin. The South Georgia Rift (SGR) was thought to be the best preserved of these basins having been capped by thick basalt flows of the Central Atlantic Magmatic Province (CAMP) and later buried beneath the Cretaceous and younger Coastal Plain. Because it is buried beneath the Coastal Plain, the SGR is only known through sparse drilling and geophysical methods. Despite this limited dataset, the SGR is the only one of the eastern North American Triassic basins known to overlie the ancient Alleghanian …

Geomechanics And Elastic Anisotropy Of The Bakken Formation, Williston Basin, Mehdi Ostadhassan

Theses and Dissertations

Many of the earth’s rocks exhibit anisotropic characteristics. Anisotropy is particularly common in many sedimentary rocks, such as shales. Anisotropy is defined as the spatial alignment of mineral grains, layers, fractures and stresses which causes elastic wave velocity and other elastic properties to vary with direction. There are two types of anisotropy: intrinsic and stress-induced. Intrinsic anisotropy is caused by beddings, microstructures or aligned fractures formed during deposition. Stress-induced anisotropy is caused by strain associated with external stresses. Intrinsic anisotropy originates in the absence of external stresses, while stress-induced anisotropy results from tectonic and overburden stresses. The style of earth …

Controlling Factors On Bedrock River Sinuosity In The Eastern Tibetan Plateau, Lydia Curliss

Honors Papers

Average sinuosity of bedrock rivers across the eastern Tibetan Plateau (including the Yangtze, Mekong, Salween, Irrawaddy, and Tsang Po) ranges from 1.20-1.41. From 25°-30°N, sinuosity marginally increases east to west; over the entire distance of each river, sinuosity increases north to south. Increases in sinuosity parallel a regional tectonic gradient in an area with a marginal climate gradient. Several past studies correlate sinuous bedrock rivers in mountainous regions with gradients in climate, arguing that landslides are the main mechanism by which bedrock rivers increase sinuosity. Other studies find correlations between tectonics and increasing landslide frequency. To investigate the role of …

Thermobarometric Modeling Of The Catalina Amphibolite Unit: Implications For Tectonic And Metasomatic Models, Henry W. Towbin

Honors Papers

On Santa Catalina Island, Ca high-grade amphibolite units overlie progressively lower- grade blueschist units in an inverted stack structure. This juxtaposition of high grade and low-grade metamorphic units has long been the subject of much debate as to the tectonic origins of the formation and how it relates to California's tectonic evolution. Previous petrography and thermobaromety of blocks in the amphibolite unit estimate pressures and temperatures of ~8-11 kbar and ~640-750 °C (Platt, 1975; Sorensen and Barton 1987). These estimates were calculated before many of the computational advances in modern thermobarometry. Using Equilibrium Assemblage Diagrams (EAD) calculated with Theriak Domino, …

Strain Energy Release From The 2011 9.0 Mw Tōhoku Earthquake, Japan, Kenneth M. Cruikshank, Curt D. Peterson

Geology Faculty Publications and Presentations

The purpose of this paper is to compare the strain energy released due to elastic rebound of the crust from the tragic 2011 9.0 Mw Tōhoku earthquake in Japan with the observed radiated seismic energy. The strain energy was calculated by analyzing coseismic displacements of 1024 GPS stations of the Japanese GEONET network. The value of energy released from the analysis is 1.75 × 1017 J, which is of the same order of magnitude as the USGS-observed radiated seismic energy of 1.9 × 1017 Nm (J). The strain energy method is independent of seismic methods for determining the energy released …

Amplitude Vs. Offset Effects On Gas Hydrates At Woolsey Mound, Gulf Of Mexico, Walter R. Anderson

Theses and Dissertations

Due to the estimated massive quantities of natural methane hydrates, they represent one of the largest sources of future alternative energy on Earth. Methane hydrates have been found in the shallow sub-seafloor of the Northern Gulf of Mexico where the water depth is in excess of ~900 m. Mississippi Canyon Block 118 has been chosen by the Gulf of Mexico Hydrates Research Consortium to be the site of a multi-sensor, multi-discipline sea-floor observatory for gas hydrate research. First evidence for gas hydrates at MC 118 was observed at Woolsey Mound. Subsurface evidence for gas hydrates has subsequently been substantiated by …

Balanced Cross Section Of The Northeast Of Adiyaman, Turkey, Mustafa Tuncer

Masters Theses

"Deformation during closure of an ocean basin and continent-continent collision in southeast Anatolia Turkey during the Late Cretaceous to Middle Miocene was investigated by construction of a geologic map, structural cross-section and retrodeformed palinspastically restored cross-section. The area of study is a N-S transect across the Bitlis Suture Zone of Northeast of Adiyaman. The study area is situated in the southeast Anatolian orogenic belt which includes, from south to north, the Arabian platform, the zone of Imbrication, and the zone of Nappes. A geologic map of this region was prepared in order to construct balanced and restored cross sections from …

3d Seismic Data Interpretation Of Boonsville Field, Texas, Aamer Ali Alhakeem

Masters Theses

"The Boonsville field is one of the largest gas fields in the US located in the Fort Worth Basin, north central Texas. The highest potential reservoirs reside in the Bend Conglomerate deposited during the Pennsylvanian. The Boonsville data set is prepared by the Bureau of Economic Geology at the University of Texas, Austin, as part of the secondary gas recovery program. The Boonsville field seismic data set covers an area of 5.5 mi². It includes 38 wells data. The Bend Conglomerate is deposited in fluvio-deltaic transaction. It is subdivided into many genetic sequences which include depositions of sandy conglomerate representing …

A Structural Analysis Of The El Kasr Structure In The Western Desert Of Egypt, Trevor Charles Ellis

Masters Theses

"The El Kasr structure was studied in order to investigate the origins and evolution of the enigmatic Desert Eyes structures of the Western Desert due to its accessibility and uniqueness among the structures. The El Kasr structure, an elongate structural basin with low limb dips, is unique among the "Desert Eyes" structures in that it: 1) occurs in isolation in otherwise horizontal sedimentary rock, 2) the long dimension of the basin is oriented NNW, 3) it is closely spatially associated with the less common NNW fault zones, and 4) is composite in nature. The structure was investigated using remote sensing …

Early Eocene To Middle Miocene Cooling And Aridification Of East Antarctica, Sandra Passchier, Steven M. Bohaty, Francisco J. Jiménez‐Espejo, Jörg Pross, Ursu Röhl, Tina Van De Flierdt, Carlota Escutia, Henk Brinkhuis

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

[1] Few high‐latitude terrestrial records document the timing and nature of the Cenozoic “Greenhouse” to “Icehouse” transition. Here we exploit the bulk geochemistry of marine siliciclastic sediments from drill cores on Antarctica's continental margin to extract a unique semiquantitative temperature and precipitation record for Eocene to mid‐Miocene (~54–13 Ma). Alkaline elements are strongly enriched in the detrital mineral fraction in fine‐grained siliciclastic marine sediments and only occur as trace metals in the biogenic fraction. Hence, terrestrial climofunctions similar to the chemical index of alteration (CIA) can be applied to the alkaline major element geochemistry of marine sediments on continental margins …

A Study Of The Impacts Of Freeze-Thaw On Cliff Recession At The Calvert Cliffs In Calvert County, Maryland, Bonnie Elizabeth Zwissler

Dissertations, Master's Theses and Master's Reports - Open

The Calvert Cliffs, which form much of the western coastline of the Chesapeake Bay in Calvert County, Maryland, are actively eroding and destabilizing, resulting in a critical situation for many homes in close proximity to the slope's crest. Past studies have identified that where waves directly interact with the toe of the slope, wave action controls cliff recession; however, where waves do not regularly interact with the slope toe, the past work identified that freeze-thaw controls recession. This study investigated the validity of this second claim by analyzing the recession rate and freeze-thaw behavior of six study sites along the …

Trophic State Monitoring Of Lakes And Reservoirs Using Remote Sensing, Michelle Aten

Electronic Theses and Dissertations

Lakes and reservoirs are important resources that provide water for critical needs, such as drinking water, agriculture, recreation, fisheries, wildlife, and other uses. However, there is increasing concern that anthropogenic eutrophication threatens the usability of these natural resources. Therefore, this research investigates these complex hydrologic ecosystems and recommends a methodology for monitoring the trophic state of lakes and reservoirs using remote sensing data. The Mississippi Department of Environmental Quality provided in situ data for seven Mississippi lakes including, Arkabutla, Bay Springs, Enid, Grenada, Okatibbee, Ross Barnett, and Sardis lakes. This research explored the relationships between the Secchi depth (SD), chlorophyll-a …

Compressional And Em Wave Velocity Anisotropy In A Temperate Glacier Due To Basal Crevasses, And Implications For Water Content Estimation, John Bradford, Joshua Nichols, Joel T. Harper, Toby W. Meierbachtol

Geosciences Faculty Publications

We have conducted a series of experiments designed to investigate elastic and electromagnetic (EM) velocity anisotropy associated with a preferentially aligned fracture system on a temperate valley glacier in south-central Alaska, USA. Measurements include a three-dimensional compressional wave (P-wave) seismic reflection survey conducted over a 300 m x 300 m survey patch, with uniform source grid and static checkerboard receiver pattern. Additionally, we acquired a multiazimuth, multi-offset, polarimetric groundpenetrating radar (GPR) reflection experiment in a wagon-wheel geometry with 94 degrees of azimuthal coverage. Results show azimuthal variation in the P-wave normal-moveout velocity of less than 3% (3765 and 3630 ms …

Hydraulic Fracturing Design For Horizontal Wells In The Bakken Formation, Williston Basin, Hadi Jabbari

Theses and Dissertations

Unconventional hydrocarbon reservoirs have proved to be challenging in terms of reservoir characterization, predicting production potential, estimating ultimate recovery, and optimizing hydraulic fracture stimulations. The methods by which these resources are extracted use progressive, or unconventional, technologies. Today, through the use of hydraulic fracturing and horizontal drilling, extraordinary amounts of oil and natural gas from deep shale formations across the United States and around the world are being safely produced.

Performing a hydraulic fracture design requires modeling of fracture propagation and tracking the fluid front in the created fracture. In this dissertation, the roles of all effective parameters and properties …

Olivine Ca Content Measured By Icp-Oes To Estimate P-T, Bradley Benavides

Open Access Theses & Dissertations

Ca is a trace element in olivine and its concentration is pressure and temperature dependent, providing a rare opportunity to estimate pressure conditions at which mantle-derived rocks (xenoliths) last equilibrated. This P-T dependence has previously been calibrated for mantle xenoliths, and we applied this technique to samples from Jasper Seamount (Jasper Seamount), an oceanic intraplate volcano (OIV) off the coast of the Baja California Peninsula of Mexico. Preliminary compositions for xenoliths from this location appear to define a magmatic plumbing system that features magma storage near the bottom of the crust. A more detailed analysis of the samples is required …

Rare Earth Element Geochemistry Of The Sierra Blanca Laccoliths, Texas, Amed Gomez

Open Access Theses & Dissertations

No abstract provided.

Depositional Setting And Sequence Stratigraphic Analysis Of The Lower Permian Lower Hueco Formation On The Western Margin Of The Orogrande Basin, South Central New Mexico, Jonathon Eric Stautberg

Open Access Theses & Dissertations

On the western margin of the Orogrande Basin in south-central New Mexico, eight outcrop datasets, in the form of measured stratigraphic sections from the lower interval of the Lower Permian Lower Hueco Formation were analyzed in regard to depositional facies distribution and sequence stratigraphy. Based on petrographic analysis of 247 samples and associated field relationships, 11 depositional facies are recognized: 1) quartz sandstone, 2) quartz siltstone and shale, 3) fenestral dolomudstone, 4) microbial intraclast packstone, 5) dolomudstone, 6) green-algal packstone to grainstone, 7) ostracode foram wackestone, 8) oolitic packstone, 9) fossiliferous packstone and grainstone, 10) fusulinid packstone and grainstone, 11) …

Physical And Sequence Stratigraphy Of The Late Cretaceous Chispa Summit Formation, Jeff Davis County, Texas, Patrick Thomas Dietzel

Open Access Theses & Dissertations

The Late Cretaceous Chispa Summit Formation of west Texas has historically been of interest to the petroleum industry; with new technologies, this old, uneconomical play could prove significant, if not for energy resources, for educational purposes, but little work has been conducted on the formation. The Eagle Ford Formation of southern Texas is time equivalent to the Chispa Summit Formation and is a highly prolific hydrocarbon resource.

Located in western Jeff Davis County, Texas, the Chispa Summit Formation consists of marine shales interbedded with limestone beds and sporadically located siliciclastic beds, measuring a total of 610 m at the type …

Geology And Geochemistry Of The Sierra Blanca Rare Earth Complex, Sierra Blanca, Texas, Nicole Kyger

Open Access Theses & Dissertations

With an increasing standard of living comes an increase in demand for high tech goods, environmentally friendly (green) and military technologies, and the inherent need to procure the necessary raw materials. Demand for the rare earth elements (REE) is on the rise, and there is no foreseeable decline in the need for accessible deposits. Between 2010 and present, the United States Congress has heard numerous reports on the importance of REE, and in 2012 the Department of Defense(DoD)declared REE a critical resource, with implications for national security. The Sierra Blanca laccoliths, 150 kilometers southeast of El Paso, TX represent a …

Geophysical Investigation And Assessment Of The Rye Patch Known Geothermal Resource Area, Rye Patch, Nevada, Mark Richmond Mcdonald

Theses and Dissertations

A gravity and ground-based magnetic survey was conducted at the Rye Patch Known Geothermal Resource Area located at Rye Patch, Nevada. The purpose of the study was to attempt to further delineate the geothermal reservoir and/or to identify potential drilling targets. The survey consisted of collecting data at 264 new stations to augment data from 203 stations collected in 2008. Information from previous seismic, aeromagnetic and geochemical investigations was also examined and incorporated. Filtering methods including removal of a polynomial trend surface and wavelength filtering were utilized on the gravity data to remove the strong regional overprint caused by the …