Geology Commons^™

Glaciovolcanic Megapillows Of Undirhliðar, Reykjanes Peninsula, Southwestern Iceland, Rachel Heineman

Honors Papers

At Undirhliðar tindar on the Reykjanes Peninsula, southwestern Iceland, megapillows are among the features formed during a series of ridge-building glaciovolcanic eruptions. Mapping of the northeastern 3 km of the ridge and petrographic and geochemical analysis of the megapillow outcrops occurring throughout this area demonstrate their role in the multi-stage construction of the ridge modeled by Pollock et al. (2014). The outcrops exhibit radial jointing, bands of vesicles and glassy rims, they occur in high relief surrounded by basalt breccia resembling pillow rubble, and are composed of plagioclase-phyric olivine basalt with plagioclase-rich groundmass. They occur in multiple pillow lava units …

Experimental Biomechanics Of Trinucleid Fringe Pits (Trilobita), Kirk Pearson

Honors Papers

The morphometric uniqueness of the trinucleid family of fossil arthropods, known as the trilobites, has led to a considerable amount of attention in paleontology literature. In particular, the distinctive hourglass-shaped pits that dot their anterior have been the subject of debate for over a century. Though anatomically well understood, their function remains unknown. Many proposals have been suggested, including its use as a sieve for filter-feeding, a strong shield for defense, and a sensory mechanism to compensate for their blindness. Despite the wide range of speculations, no study has attempted to model these hypotheses experimentally. Flume experiments and mechanical strength …

Lithologic Stratigraphic Position, Sequence And Diagenetic History, Lower Mississippian Tripolitic Chert, Northern Arkansas And Southern Missouri, S. Mckim, J. Cains, J. Chick, F. Mcfarlin, A. Potra

Journal of the Arkansas Academy of Science

Tripolitic chert development in the southern Ozark region is associated with a third-order, transgressive-regressive cycle comprising St. Joe transgressive packstones, succeeded by lower Boone calcisiltites, with black, penecontemporaneous, nodular chert deposited during maximum flooding, overlain by basal upper Boone calcisiltites deposited during highstand. The onset of regression produced upper Boone packstones and grainstones with white-gray, later diagenetic chert reflecting groundwater replacement along bedding planes. Tripolitic chert is a product of the highstand calcisiltites at the base of the upper Boone Formation of Arkansas, and its equivalent, the Elsey Formation of southern Missouri. This tripolitic chert appears to reflect a hydrothermal …

Hydrothermally Emplaced, Lower Mississippian, Tripolitic Chert And Its Possible Relationship To The Tri-State Lead-Zinc Mining District, J. Chick, J. Cains, F. Mcfarlin, S. Mckim, A. Potra

Journal of the Arkansas Academy of Science

Across the southern Ozark Region, northern Arkansas, southwestern Missouri, and northeastern Oklahoma, exposures of the Lower Mississippian Boone Formation and its equivalents exhibit well-developed tripolitic chert that has been mined, more or less continuously, for at least 80 years. The tripolitic chert is a replacement of an interval within the basal portion of the upper Boone Formation in Arkansas and Oklahoma, and equivalent to the Elsey Formation in Missouri. The movement of silica-rich, hydrothermal fluids appears to have been much like that of a confined aquifer. It followed the basal upper Boone Formation (Arkansas) = Elsey Formation (Missouri) and was …

Carbon Sources To Microbes And Cryoconite On Alaskan Alpine Glacier Surfaces, Drake Mccrimmon

Theses and Dissertations

Cryoconite are depressions in the ice surface filled with diverse microorganisms and dark debris, which are reducing albedo and increasing glacier melt. In order to understand cryoconite carbon composition and carbon sources to microorganisms living on glacier surfaces, bulk organic carbon and microbial lipids from supraglacial cryoconite sediment within the ablation zones of Spencer, Matanuska, and Mendenhall glaciers in southern Alaska have been coupled with radiocarbon (14C) analyses. The microbial lipids analyzed in these studies, phospholipid fatty acids (PLFA), are components of microbial membranes, quickly degrade after cell death, and give a snapshot of the viable microbial community. PLFA structure …

Geophysical Interpretation And Static Reservoir Modeling Of Structurally Complex Reservoir, Rg Oil Field Area, Sirte Basin, Libya, Abdalla A. Abdelnabi

Doctoral Dissertations

"Cambrian-Ordovician and Upper Cretaceous reservoir formations are found in the central western Sirte Basin, the main oil producing region in the Sirte Basin, Libya. As a result of changes in sedimentary environments and structural activities, a number of irregularities in reservoir continuity have developed, which negatively affected the overall performance of the reservoir. Effective simulation of such complex reservoirs can be achieved by integrating geophysical, geological, and petrophysical data to construct a reliable full-field static model, which has the potential to simulate the vertical and lateral variations in the reservoir formations. In this study, 2D and 3D seismic data acquired …

Assessment Of Rockfall Rollout Risk Along Varying Slope Geometries Using The Rocfall And Crsp Software, Mariam S. Al E'Bayat

Masters Theses

"Most routes in mountainous areas suffer from rock falling, rolling and bouncing risk. There are many computer programs concerned with simulating the rockfall problem, and whereas they have the same purpose, they however differ in the input data that's needed to simulate the problem, and they also differ in the way of processing and kind of output.

This study used Rocfall® and the Colorado Rockfall Simulation Program (CRSP®) to simulate sixty-three models of varying slope geometry, where only the slope geometry is changed with the same material properties for both the slope and the rocks.

Both programs were fast and …

Deformation Processes At The Leading Edge Of The Sevier Fold And Thrust Belt, Southwest Utah, William Joseph Michael Chandonia

Masters Theses

"Deformation processes leading to formation and abandonment of 'triangle zones' along the leading edge of the Sevier fold and thrust belt are investigated near Kanarraville, Utah through construction of a detailed geologic map and cross-section along Spring Creek. Here the eastern limb of the Kanarra fold, a Sevier structure, is well exposed along the Hurricane Cliffs due to uplift and erosion of the footwall of the Hurricane Fault. The east-verging Kanarra fold changes from upright to overturned within Spring Creek. Within the fold limb, parasitic folds, minor thrust faults, and duplex structures result in local tectonic overthickening of units and …

Structural And U-Pb Detrital Zircon Geochronologic Constraints On The Origin Of The Condrey Mountain Schist, California - Oregon, Joseph Reid Coons

Masters Theses

"The Condrey Mountain Schist (CMS) of the Klamath Mountains (northern California and southern Oregon) represent low grade oceanic and terrigenous sediments thrust beneath higher grade ophiolitic rocks of the Rattlesnake Creek Terrane (RCT). This study presents new U-Pb detrital zircon dates from the CMS, and from the possibly correlative basin rocks of the Galice Formation and accretionary rocks of the South Fork Mountain Schist. The Galice Formation yields a maximum depositional age of ca. 152 Ma with prominent date distributions of ca. 150-200 Ma (39% of analyzed grains), 200-600 Ma (1%), 600 - 1000 Ma (2%), and 1000-3200 Ma (58%). …

Provenance And Depositional Environments Of Fluvial-Lacustrine Deposits In A Non-Marine Rift Basin, Lower-Triassic Jiucaiyuan And Shaofanggou Low-Order Cycles Bogda Shan, Nw China, Jaimeson Grigaitis Fredericks

Masters Theses

"The uppermost Carboniferous to Lower Triassic eolian-fluvial-lacustrine deposits of Turpan-Junggar Basin, NW China, record the non-marine sediment-filling processes in a continental rift basin in mid-latitude NE Pangea. This study focuses on the fluvial-lacustrine strata of the Lower Triassic Jiucaiyuan (JCY) and Shaofanggou (SFG) low-order cycles (LCs) in multiple half grabens at the southern and northern foothills of Bogda Shan. Outcrop, paleocurrent, and petrographic analyses indicate a southern provenance. Intermediate to felsic volcanic lithics and metamorphic lithics are interpreted as being derived from Tian Shan to the south while the sedimentary lithics originate from the local rift shoulders. The basaltic lithics …

Evaluation Of Swelling And Re-Swelling Of Preformed Particle Gels (Ppg) When Exposed To Co₂, Sujay Suresh

Masters Theses

"Long term water/gas flooding induces high permeability channels in reservoirs. Reservoir heterogeneity becomes the most prominent challenge faced in mature oil fields. Gel treatment has been a proven solution to counter the problem of reservoir heterogeneity, to provide in-depth treatment and improve the sweep efficiency for reservoirs. Preformed particle gels (PPGs) were developed as an alternative to in-situ gels as they preferentially penetrate and shutoff high permeability zones, leaving the low permeability zones undamaged. These gels have been predominantly used in water flooding projects, but have not been employed in carbon dioxide (CO₂) flooding projects. CO₂ Resistant …

Development Of A Variogram Approach To Spatial Outlier Detection Using A Supplemental Digital Elevation Model Dataset, Zane Daniel Helwig

Masters Theses

"When developing a ground water model, the quality of the dataset should first be evaluated. Spatial outliers can lead to predictions which are not representative of actual conditions. In order to isolate misrepresentative points, a method is presented which examines the experimental variogram of a ground water elevation dataset. To define a threshold variance between pairs of ground water elevation measures, ground elevation values from a digital elevation model (DEM) are used to determine a maximum reasonable variance expected to occur on the experimental variogram. To determine appropriate DEM parameters, a separate study was also done which observed characteristic behavior …

Mining Asteroids For Volatile Resources: An Experimental Demonstration Of Extraction And Recovery, Egboche Christopher Unobe

Masters Theses

"Gaseous compounds trapped within carbonaceous asteroids may prove to be important targets for prospective space miners in the near-term. Volatile release is from hydrated, hydroxylated and carbonated phases present, making such bodies attractive as feedstock for the production of H₂O, CO₂ and simple organic compounds. A source of these species in orbit provides an opportunity to locally produce space-craft propellant and other life-support gases through the application of In-situ Resource Utilization (ISRU).

For this study, an experimental vacuum system was modified and used to test the technical validity of radiatively heating asteroid simulants to extract contained gaseous …

Crustal Thickness And Vp/Vs Ratio Of Yellowstone, Eastern Snake River Plain, Wyoming Province, And The Northern Basin And Range Province Through Receiver Function Analysis, Avikant Dayma

Masters Theses

"For decades, numerous studies have been conducted and contradictory results were achieved about the origin and evolution of the Yellowstone supervolcano and the Eastern Snake River Plain. Whether the 640 km long time-progressive chain of rhyolitic calderas was formed due to mantle-plume or a result of lithospheric extension allowing the emergence of melt on the surface is still a debate. Using receiver function analyses, this study determines the crustal thickness and the Vp/Vs ratio below the Yellowstone Plateau, Wyoming Province (WP), Idaho Batholith (IB), Eastern Snake River Plain (ESRP), and the northern Basin and Range Province (BRP). The thickness is …

Why Now?: A Case Study Of Split Estate And Fracking Activity In Garfield County Colorado, Janessa Zucchetto

All Master's Theses

This research examines the socio-environmental impacts associated with hydraulic fracturing activities and issues of split estate in Battlement Mesa Planned Unit Development in Garfield County, CO. Data for this research was collected during 2 months in the summer of 2015 using a series of ethnographic research methods. In doing so, this research adopts political ecology and political economy of nature as theoretical frameworks to understand the interconnections that exist between local impacts of fracking activities and a national strategy to secure gas markets internationally. I argue that the socio-environmental impacts associated with hydraulic fracturing in Garfield County, CO are not …

Catastrophic Landscape Modification From Massive Landslide Tsunamis: An Example From Taan Fiord, Alaska, Colin Bloom

All Master's Theses

The October 17^th 2015 Taan landslide and tsunami generated a high runup of 192 m, nearly an order of magnitude greater than most previously surveyed tsunamis. Extensive modifications observed and documented on several low gradient fan deltas within the fiord make Taan Fiord an excellent laboratory for characterizing geomorphic signatures of a high runup tsunami event. Although interest in this topic is high, most prior post-tsunami surveys are from earthquake-generated tsunamis with relatively low runup, thus the geomorphic signatures of high runup tsunamis or their potential for preservation are uncharacterized. Additionally, clear modifications described during post-tsunami surveys are typically …

Comparing Field And Laboratory Measurements Of Hydraulic Conductivity In The Mississippi Delta, Taylor Moore

Honors Theses

This research is part of a wider effort to investigate the decreasing water levels of the Mississippi River Valley Alluvial Aquifer (MRVAA), which is partially located in the Mississippi Delta in northwestern Mississippi. The extent of this research compares laboratory and field based measurements of saturated hydraulic conductivity, known as Ksat, in the vadose zone of the Delta. The soil samples used for the laboratory Ksat tests and textural analysis were collected at various depths from two boreholes near Sky Lake in Belzoni, Mississippi. Each sample was classified by Unified Soil Classification System (USCS) standards after being sieved and tested …

Assessment Of Vadose-Zone Wells For Enhancing Groundwater Recharge In The Mississippi Delta, Luke Jenkins

Honors Theses

Current pumping rates in the Mississippi River Valley Alluvial Aquifer in the Mississippi Delta are unsustainable as they are depleting the water level in the aquifer. The following thesis is a feasibility analysis on groundwater recharge to the Mississippi River Valley Alluvial Aquifer using vadose zone wells. Two days were spent in the field at Sky Lake near Belzoni, Mississippi, collecting core soil samples, bag soil samples, and constant head hydraulic conductivity values. Numerous days were spent in the lab conducting sieve analyses, Atterberg limits, and falling head hydraulic conductivity tests. The Atterberg limit test and sieve analyses were used …

A Spatial Analysis Of Climate Change Effects On Maize Productivity In Kenya, Dan Wanyama

Theses

Climate change has intensified the risk of catastrophic natural disasters all over the world. Though impacts of the change are global, developing countries are more at risk. Although agriculture remains the backbone of Kenya’s economy, the sector’s dependence on natural resources increases its vulnerability to the aggravating impacts of climate change and variability. Climate system variations that impact staple food crops like maize (Zea mays) ultimately threaten the food security of the nation. This study examined environmental factors affecting maize productivity through regression analysis. A GIS suitability model for maize was also developed to identify Kenya’s different levels of suitability …

Geologic Map Of The Lima Peaks 7.5' Quadrangle, Beaverhead County, Montana, Betty Skipp, William J. Perry Jr., Susanne U. Jänecke

Geosciences Faculty Publications

The Lima Peaks quadrangle is located in southwestern Beaverhead County in southwestern-most Montana, near the southern terminus of the Beaverhead Mountains (fig. 1). Rocks and deposits of Mississippian through Quaternary age are present along the eastern margin of the Cretaceous to early Tertiary Sevier fold-and-thrust belt. This area is structurally complex because rocks of older, Laramide Blacktail-Snowcrest uplift (Perry and others, 1988; Skipp, 1988; Lonn and others, 2006).