Physical Sciences and Mathematics Commons^™

Evaluating Snowmelt Runoff, Infiltration, And Erosion In A Sagebrush-Steppe Ecosystem, Eric K. Duffin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Production of low-level radioactive waste (LLRW) has created a need for safe storage facilities. These facilities must be capable of isolating radioactive waste and preventing contamination from physical or biological intrusion until the waste material is isotopically stable. At the present time, managers of the Idaho National Engineering and Environmental Laboratory (INEEL) have a substantial database characterizing rainfall events and the subsequent impact on integrity of shallow land burial sites used for storage of LLRW. Little information has been gathered describing the processes of snow accumulation/ablation and the resulting impact on storage facilities. This study examines snowmelt runoff, infiltration, and …

Sequence Stratigraphy And Paleoecology Of The Middle Cambrian Spence Shale Member Of The Langston Formation Of Northeastern Utah And Southeastern Idaho, Scott H. Wright

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Middle Cambrian Spence Shale Member contains meter-scale, shallowing-up cycles (parasequences) and record approximately 360 ky of deposition. These meter-scale cycles are nested within transgressive systems tracts (TST) and highstand systems tracts (HST) which reflect different stages of a lower-order, higher-magnitude sea-level excursion.

Fossil assemblages are located in stratigraphic positions within the Spence Shale Member that can be predicted on the basis of sequence architecture. The cycle architecture, taphonomy, and geochemistry of the Spence parasequences confirm synthetic sections and theoretical models of meter-scale cycles developed in other studies. Delineation of meter-scale cycles, based on taphonomic and sedimentologic criteria, allows high-resolution …

Investigation Of The Determinants Of African Savanna Vegetation Distribution: A Case Study From The Lower Omo Basin, Ethiopia, Catherine A. Schloeder

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Ethiopian Wildlife Conservation Organization has little information on the extent and ecological determinants of plant species composition and distribution in Omo National Park. Elsewhere, the determinants of African savanna vegetation dynamics have been the focus of numerous investigations, yet our understanding of the hierarchical nature and relative importance of any relationships remains very general. As well, our ability to derive predictions about vegetation responses is limited to extreme generalizations. African savanna landscape ecotones have received even less attention than most landscapes. In this dissertation, I test hypotheses about plant species distribution-determinant relationships in Omo National Park, a park that …

Ultraviolet-B Radiation: Effects On Pollen Of 34 Taxa, And Inheritance Patterns And Carryover Of Radiation Response In Arabidopsis, Javad Torabinejad

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although considerable research has addressed effects of elevated ultraviolet-B (UV-8) radiation on vegetative plant structures and processes, the reproductive biology and patterns of inheritance of UV-B tolerance have received much less attention. I examined the effects of UV-B radiation on pollen of 34 taxa. I also addressed questions concerning the patterns of inheritance of UV-B tolerance in Arabidopsis thaliana and examined potential cumulative carryover effects of UV-B exposure through multiple generations of this species.

In the first study, a significant reduction in pollen germination occurred in only five species, but pollen tube growth in more than half of the species …

Tertiary Stratigraphy And Structural Geology, Wellsville Mountains To Junction Hills, North-Central Utah, Kathryn M. Goessel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study integrates detailed mapping of Tertiary deposits along the divide between the lower Bear River basin and the Cache Valley basin with several other techniques to generate a depositional model, define extension-related structures, and compile a geologic history for this part of the northeastern Basin and Range province. The study area is situated along the topographic divide between Box Elder and Cache Counties, Utah, from the Wellsville Mountains north almost to Clarkston Mountain. These ranges are cored by folded and thrusted Paleozoic rocks. They are bound on the west by normal faults of the Wasatch fault zone and on …

Quaternary Amino Acid Geochronology Of The Lahontan Basin, Nevada, And The Chewaucan Basin, Oregon, Jeffrey Bigelow

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Amino acid geochronology based on fossil molluscs provides a useful approach to determining the Quaternary history of Great Basin lakes. The Lahontan basin, Nevada, and the Chewaucan basin, Oregon, in the northwest corner of the Great Basin, both contained lakes during the Quaternary. The aim of this study is to improve the Quaternary geochronology in these two basins by measuring time-dependent changes in amino acids preserved in fossil molluscan shells. The abundance of D-alloisoleucine relative to Lisoleucine (All) characterizes the extent of racemization, which increases with age and Ul forms the basis of relative and correlated ages. An age-calibration curve …

Three-Dimensional Structure Of Small Strike-Slip Fault Zones In Granitic Rock: Implications For Fault-Growth Models, Kim R. Robeson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three small strike-slip fault zones exposed in granitic rock in the central Sierra Nevada, California, provide field-based data to construct three-dimensional representations of each fault zone in order to compare with the geometries predicted by existing fault-growth models. All three fault zones are nearly vertical, strike -N60°E, and have left-lateral slip. The fault zones range from 60 to 140 m in length and 1 to 12 m wide. Each fault zone consists primarily of parallel to subparallel fracture and fault traces 2 to 56 m long and is separated 25 cm to 7 m by intact rock. One fault zone …

Late Pleistocene Glacial Chronology Of The Western Ahklun Mountains, Southwestern Alaska, Jason P. Briner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

New glacial mapping and 35 cosmogenic ³⁶Cl surface exposure ages, the first ever reported from Alaska, constrain the extent and timing of late Pleistocene glacial fluctuations in the western Ahklun Mountains, southwestern Alaska. Morphometric and soil relative-age data characterize two main drift units deposited during the Arolik Lake and Klak Creek glaciations, named herein. During the Arolik Lake glaciation (early Wisconsin), outlet glaciers emanated from an ice cap over the central portion of the Ahklun Mountains and deposited moraines at or beyond the modern coast. These moraines have slope angles averaging about 11° and crests averaging about 35 m …

The Role Of An Invasive Exotic Plant On The Structure Of Aquatic Invertebrate Assemblages: Tamarix In The Southwest United States, Bert Lewis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over the past 100 years, riparian vegetation communities throughout the Southwest United States have been extensively invaded by Tamarix spp. (saltcedar). Saltcedar derives its common name from its physiological adaptation to excrete salts. The production of Tamarix detritus with associated secondary chemicals may affect the quality of aquatic invertebrate food and habitat resources. An alteration in food and habitat quality may affect the composition and structure of aquatic invertebrate assemblages.

A series of experiments was conducted contrasting aquatic invertebrate assemblage densities, colonization rates, and growth rates associated with Tamarix versus native vegetation, Populus fremontii (cottonwood) and Salix exigua (willow), to …

All-Sky Measurements Of The Mesospheric "Frontal Events" From Bear Lake Observatory, Utah, Seon-Hee Seo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies of internal gravity waves in the earth's upper atmosphere are of considerable interest. These waves play a very important role in the dynamics of the mesosphere and lower thermosphere (ML T) region where they can transfer large amounts of energy and momentum from the lower atmosphere via wave saturation and dissipation. In particular, small-scale short-period ( < 1 hour) waves of the type regularly recorded by all-sky nightglow imagers operated by Utah State University (USU) are known to be very important contributors. In this thesis attention is focused on a subset of small-scale wave phenomena recently discovered using such image data, the so called "frontal events." Frontal events have distinguishable characteristics from usual short-period ( < 1 hour) gravity waves. The principal characteristics are a well defined leading "front, " which exhibits a sharp change in intensity followed by a coherent wave trail (often extending from horizon to horizon) and relatively high phase speeds ( > 50ms^-1) Another unusual characteristic of "frontal events" is an apparent reversal in contrast of the wave structures as imaged in the hydroxyl (OH) emission (peak altitude - 87 km) when compared with the oxygen (OJ) "green line" (557.7 nm) emission (peak …

Utilization Of Spatially Distributed Soil Resources By Several Species Common To The Great Basin, Sarah Duke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Heterogeneous spatial and temporal distributions of soil resources important to plant growth have been documented in the sagebrush steppe ecosystem. There can exist as much variability in soil resources within the root zone of individual plants as exists across an entire field. The objective of this dissertation research was to evaluate how plants respond to, utilize and influence the spatial heterogeneity of soil resources. The three specific sets of questions addressed are outlined in the three main chapters of this dissertation.

My first study addressed how the number and concentration of phosphorus (P) patches in the root zone of an …

Perceived Fairness And Effectiveness Of Rangeland Collaborative Processes, Kimberly J. Richardson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Involvement in collaborative partnerships in natural resource management has become a popular method for natural resource management agencies to collect public input, cope with conflicts, and develop ecosystem management plans. This thesis evaluates various collaborative processes, emphasizing multiple-owner partnerships. Qualitative interviews of 46 landowners in Utah were conducted to reveal concerns and suggestions regarding multiple-owner landscape-level collaborative partnerships. Landowners were concerned about private property rights infringement and losing control of their private land. Landowners were primarily concerned about the fairness and effectiveness of any partnership in which they were involved.

However, they were willing to consider participating if certain procedural …

Small Strike-Slip Faults In Granitic Rock: Implications For Three-Dimensional Models, Siang Joo Lim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The geometry and mineralization features of small left-lateral strike-slip faults and associated fractures in Lake Edison Granodiorite of the central Sierra Nevada, California, were examined in order to model the three-dimensional structure of strike-slip faults. These faults, which are reactivated joints, were also examined to determine fault sizes, starting joint size, and evidence for fluid flow.

The associated secondary fractures are usually found in the dilational quadrants of fault-tip regions. The longest fault-segment trace is 32.14 m; the longest joint trace is 22 m. The joint population length (l) is represented by a power-law distribution (l^{-n …}

On The Model Selection In A Frailty Setting, Jill F. Lundell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

When analyzing data in a survival setting, whether of people or objects, one of the assumptions made is that the population is homogeneous. This is not true in reality and certain adjustments can be made in the model to account for heterogeneity. Frailty is one method of dealing with some of this heterogeneity. It is not possible to measure frailty directly and hence it can be very difficult to determine which frailty model is appropriate for the data in interest. This thesis investigates three model selection methods in their effectiveness at determining which frailty distribution best describes a given set …

Statistical Characterization Of Fluvial-Deltaic Reservoirs With Archetypes, Laura L. Watkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Optimizing the extraction of oil and other hydrocarbon products from existing sites is important. One source of hydrocarbon products is reservoirs found within sedimentary rock formations. Understanding fluid behavior within such formations can be quite useful in optimizing oil production. Fluid behavior within sedimentary formations is influenced by the bedform structure and permeabilities within the formation. Thus, we are concerned with developing a physically and statistically valid method of characterizing sedimentary rock formations. The use of archetypal analysis to generate synthetic bedforms, as well as the use of Kriging to assign permeabilities within a bedform, was explored. With these tools, …

Quaternary Bear River Paleohydrogeography Reconstructed From The 87sr/86sr Composition Of Lacustrine Fossils, David P. Bouchard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Diverted from its former course to the Pacific Ocean by basalt flows in Gem Valley, Idaho, the Bear River presently flows south into the Bonneville Basin. Constraining the timing of the river's diversion is pivotal to understanding the hydrologic budgets, and thus the climatological implications of the Bonneville Basin lakes. This study employs strontium (Sr) isotopes in mollusc fossils as a tracer of the Bear River water that entered Lake Thatcher, a small, closed-basin lake into which the redirected river flowed en route to the Bonneville Basin. The Sr ratios, combined with the temporal control afforded by amino acid geochronology …

A Hydrogeochemical Study Of The Evolution Of The Headwaters Of The Bear River In The Uinta Mountains, Utah, Michael F. Leschin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The headwaters of the Bear River in the Uinta Mountains of Utah provide a good setting in which to examine the influence of geological materials on stream chemistry. Ionic contributions to the stream-water from soils, vegetation, and the atmosphere generally are sparse enough that they do not mask the geologic contributions. Samples from 37 sites on the four major headwater streams and several minor tributaries were examined geochemically. Data derived from the samples allowed the construction of a hydrogeochemical weathering model specific to the study area. A significant feature of this model is that carbonic acid is the dominant chemical …

Geometric Aspects Of Second-Order Scalar Hyperbolic Partial Differential Equations In The Plane, Martin Jurás

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this dissertation is to address various geometric aspects of second-order scalar hyperbolic partial differential equations in two independent variables and one dependent variable

F(x, y, u, u_x, u_y, u_xx, u_xy, u_yy) = 0

We find a characterization of hyperbolic Darboux integrable equations at level k (1) in terms of the vanishing of the generalized Laplace invariants and provide an invariant characterization of various cases in the Goursat general classification of hyperbolic Darboux integrable equations (1). In particular we give a contact invariant characterization of equations integrable by …

Identification Of Belowground Woody Structures Using Molecular Biomarkers, Benny R. Bobowski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Within the last two decades substantial progress has been made in understanding seed bank dynamics and the contribution of the soil seed bank to a post-disturbance plant community. There has been relatively little progress, however, in understanding perennial bud bank dynamics and the contribution of the soil bud bank to secondary succession. This lack of information is due primarily to the inability to reliably identify roots, rhizomes, and lignotubers that lie dormant beneath the soil surface. This scientific investigation, therefore, addressed the issue of identification of belowground woody structures.

The first objective was to develop a methodology that utilizes molecular …

Modelling Vegetation Cover Types Using Multiseasonal Remotely Sensed Data To Compare Ecotones At Multiple Spatial And Spectral Resolutions, Kimberly Patraw

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Army National Guard Bureau has implemented a cooperative project with Utah State University to help with the use, display, and evaluation of environmental data for maintaining land condition. Camp Grayling, Michigan, is comprised of deciduous and evergreen forest types. Use of remote sensing for classification has been limited in this region due to the difficulty of species-level classification using single-date remote-sensing techniques. Also, remote sensing has traditionally focused on mapping homogenous zones rather than vegetation boundaries, while one of the concerns for land managers is the nature of vegetation edges (ecotones).

This study analyzed each season and band from …

Channel Narrowing Of The Green River Near Green River, Utah: History, Rates, And Processes Of Narrowing, Tyler M. Allread

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Previous scientific research has documented channel narrowing on the Green River near Green River, Utah, but the exact timing, rates, and causal mechanisms of that narrowing have been the source of disagreement in the scientific literature. This thesis demonstrates that the Green River has narrowed in two separate periods during the last 100 years. The narrowing is driven primarily by changes in the hydrologic regime and not by the invasion of saltcedar. The channel narrowed between 1930 and 1938, when a shift from wetter than normal conditions to a period of draught led to a reduction in river discharge. Channel …

Cenozoic Tectonic And Paleogeographic Evolution Of The Horse Prairie Half-Graben, Southwest Montana, Colby J. Vandenburg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Horse Prairie basin (HPB) of southwestern Montana is a complex, east dipping half-graben that contains three angular unconformity-bounded sequences of Tertiary lacustrine, paludal, and fluvial sediments overlying middle Eocene volcanic rocks. The basin is near the eastern edge of the Cordilleran thrust belt, and represents the western half of a larger Paleogene rift basin. Geologic mapping within the Everson Creek and Bannock Pass 7.5 minute quadrangles indicates that five temporally and geometrically distinct episodes of extension characterize the late Mesozoic (?) to Cenozoic tectonic evolution of the upper HPB.

The first episode of extension occurred prior to emplacement of …

Studies Of Mid-Latitude Mesospheric Temperature Variability And Its Relationship To Gravity Waves, Tides, And Planetary Waves, Kenneth C. Beissner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Temperature observations of the middle atmosphere have been carried out from September 1993 through July 1995 using a Rayleigh backscatter lidar located at Utah State University (42°N, 111°W). Data have been analyzed to obtain absolute temperature profiles from 40 to 90 km. Various sources of error were reviewed in order to ensure the quality of the measurements. This included conducting a detailed examination of the data reduction procedure, integration methods, and averaging techniques. eliminating errors of 1-3%. The temperature structure climatology has been compared with several other mid-latitude data sets. including those from the French lidars, the SME spacecraft, the …

Empirical Studies Of Ionospheric Electric Fields, Ludger Scherliess

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The first comprehensive study of equatorial- to mid-latitude ionospheric electric fields (plasma drifts) is presented, using extensive incoherent scatter radar measurements from Jicamarca, Arecibo, and Millstone Hill, and F-region ion drift meter data from the polar orbiting DE-2 satellite. Seasonal and solar cycle dependent empirical quiet-time electric field models from equatorial to mid latitudes are developed, which improve and extend existing climatological models. The signatures of electric field perturbations during geomagnetically disturbed periods, associated with changes in the high-latitude currents and the characteristics of storm-time dynamo electric fields driven by enhanced energy deposition into the high-latitude ionosphere, are studied. Analytical …

Effects Of Flow Augmentation On Channel Morphology And Riparian Vegetation In The Upper Arkansas River Basin, Colorado, Dewitt S. Dominick

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined historic change of riparian plant communities and fluvial geomorphic response of gravel-bedded streams and their floodplains to over 50 years of hydrologic disturbance. Four tributary basins of the Arkansas River were analyzed. Lake Creek, Clear Creek, and Cottonwood Creek are drainages similar in area, physiography, and vegetation composition. However, Lake Creek may receive an instantaneous discharge of approximately 28 m3sec^-1 from the Twin Lakes tunnel, over three times the normal flow of the stream during spring runoff. By contrast, Clear Creek and Cottonwood Creek, nonaugmented streams, were used as controls to compare the historic and present …

Stratigraphy, Geochronology, And Tectonics Of The Salt Lake Formation (Tertiary) Of Southern Cache Valley, Utah, Kristine A. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study synthesizes the deposition and tectonic evolution of the Tertiary deposits in southern Cache Valley, a narrow, north-trending valley in the northeastern Basin-and- Range Province. The surrounding mountains consist of Proterozoic and Paleozoic sedimentary rocks. Southern Cache Valley is an east-tilted half-graben. The oldest Tertiary sediments are on the west side of the basin, and the overall dip is to the east.

The Late Miocene to Early Pliocene Salt Lake Formation (Tsl) accumulated above the thin (to absent) Early to Middle Eocene Wasatch Formation (Tw) and the newly identified Fowkes and Norwood Tuff equivalents (Tfn; late Middle Eocene to …

Geomorphology Of The Green River In Dinosaur National Monument, Paul E. Grams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Longitudinal profile, channel cross-section geometry, and depositional patterns of the Green River in its course through the eastern Uinta Mountains are each strongly influenced by river-level geology and tributary sediment delivery processes. We surveyed channel cross sections at 1-km intervals, mapped surficial geology, and measured size and characteristics of bed material in order to evaluate the geomorphic organization of the 70- km study reach. Canyon reaches that are of high gradient and narrow channel geometry are associated with the most resistant lithologies exposed at river level and the most frequent occurrences of tributary debris fans. Meandering reaches that are characterized …

Geochemical, Petrologic, And Structural Characterization At Multiple Scales Of Deformation Associated With The Punchbowl Fault, Southern California, Steven E. Schulz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three traverses across the exhumed trace of the Punchbowl fault zone in the Pelona Schist, southern California, were examined at the millimeter to kilometer scales to determine the morphology, deformation mechanisms, and geochemistry of the fault zone in schistose rocks. The Pelona Schist is predominantly a quartz-albite-muscovite-actinolite schist with associated minor metabasalts. The Punchbowl fault zone, which is exhumed 2-4 km, has 44 km of right lateral slip, and is composed of a fault core enveloped by a damaged zone.

The fault core is a region of extreme slip localization that records most fault displacement. Deformation in the fault core …

The Geomorphic Basis Of Colorado Squawfish Nursery Habitat In The Green River Near Ouray, Utah, Cynthia L. Rakowski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nursery habitat availability is considered a bottleneck to successful recruitment of Colorado squawfish (Ptychocheilus Lucius). Detailed geomorphic studies were conducted in a 1.5-km reach to examine channel response to flows and the geomorphic setting of nursery habitats during a 2-year period. Videography was used to extend relationships in the 1.5-km reach to a longer 10-km reach.

Nursery habitat availability varied yearly with little persistence in location or geomorphic setting of individual habitats for the 2 years of this study. A small number of habitats provided most of the area of high-quality (i.e., deep) habitat, and most of the …

A Slow-Release Nitrogen Fertilizer: Ammonium-Loaded Clinoptilolite, T. Scott Perrin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Crops grown in sandy soils require frequent irrigation. As a result, nitrogen (N) fertilizers. such as ammonium sulfate((NH₄)₂SO₄), are leached from the rooting zone of crops. This loss of N increases N fertilizer use and the potential for nitrate (NO₃^-) contamination of water. Ammonium-loaded clinoptilolite (NH₄⁺-Cp) may reduce this N leaching, increase N fertilizer use-efficiency, and prevent NO₃- contamination of water while sustaining normal crop growth.

The potential of NH₄⁺-Cp as a N fertilizer was assessed in three leaching experiments without plants and …