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Seismic Field Survey Of The Ground Of The National Research Institute Of Astronomy And Geophysics, Mohamed Said Hanno

Archived Theses and Dissertations

No abstract provided.

Origin And Tectonic Evolution Of Gondwana Sequence Units Accreted To The Banda Arc: A Structural Transect Through Central East Timor, Elizabeth Anick Zobell

Theses and Dissertations

Petrographic and age analysis of sandstones, detailed structural analysis and gravity modeling were conducted to investigate the origin of the Gondwana Sequence in the Timor Region, and to better constrain the tectonic evolution of the active Banda Arc. Our field studies and U/Pb zircon age analysis helped assign most units to either Asian or Australian affinity. Detrital zircon from uplifted Banda forearc units (Asian affinity) have U/Pb ages as young as 80 Ma (Standley and Harris, in press). In contrast, analysis of detrital zircon from Gondwana Sequence sandstones accreted to the Banda Arc from Savu to East Timor are no …

Kinematic And Tectonic Significance Of The Fold- And Fault- Related Fracture Systems In The Zagros Mountains, Southern Iran, Katayoun Mobasher

Geosciences Dissertations

Enhancement methods applied on various satellite images (ASTER, ETM and RADAR SAT-1) facilitated the identification and mapping of tectonic fractures in the Zagros fold-and-thrust belt in southwest Iran. The results of the fracture analysis on these enhanced images reveal four principal fracture sets within each fold structure: (i) an axial set defined by normal faults oriented parallel to the fold axial trace, (ii) a cross-axial, extensional fracture set oriented perpendicular to the fold axial trace, (iii) and two sets of intersecting shear fractures, oriented at an acute angle to the cross-axial set. Study of the enhanced images also revealed five …

High-Resolution Stratigraphy At A Coastal Drillhole, Beth Wrege

All Theses

Lithologic descriptions of continuous core interpreted in conjunction with borehole geophysical logs were used to determine thicknesses of hydrologic and geologic units at CR-622 in the coastal plain of North Carolina. Borehole geophysics was used to adjust the position of core loss within each cored interval and to supplement lithology to determine the stratigraphy of missing segments of core. Although some geophysical logs produce non-unique lithologic solutions, a complete normal stratigraphic profile may be obtained with the addition of continuous core. Curve characteristics within geophysical logs provide precise identification of transitional sequences and can be used to calibrate lithostratigraphy. The …

Remote Sensing Of Impact Crater-Exposed Subsurface Lithologies And Martian Rayed Crater Systems, Livio Leonardo Tornabene

Doctoral Dissertations

Impact cratering is ubiquitous, energetic and fundamental geologic process acting on the solid planetary bodies. As a consequence, craters provide planetary scientists with useful information regarding the surface and subsurface properties of planetary bodies. Specific mineral and lithologic compositions can be ascertained via craters in two ways: 1) by the remote sensing of crater-exposed subsurface materials, or 2) by studying the differentiated meteorites (e.g., lunar, Martian, etc.) ejected from their surfaces by highenergy impacts under specific conditions. As a proof of concept for subsurface-crater mapping, remote sensing techniques were applied to a terrestrial impact structure. Visible-near infrared (VNIR), short-wavelength infrared …

Beauveria Bassiana, A Cotton Endophyte With Biocontrol Activity Against Seedling Disease, Mary Ruth Griffin

Doctoral Dissertations

Beauveria bassiana isolate 11-98 is entomopathogenic, endophytic in tomato, and has biocontrol activity against Rhizoctonia solani on tomato. The objectives of this study were to determine 1) if B. bassiana is endophytic in cotton, following seed treatment; 2) if B. bassiana can protect cotton against seedling pathogens; 3) if different conidial rates, applied to seed, alter effectiveness of B. bassiana; and 4) mechanisms of biocontrol used by B. bassiana against plant pathogens. Cotton ‘Delta Pine 436’ seed was inoculated with isolate 11-98 conidia, sown in a gnotobiotic system, and then isolated from surfacesterilized seedlings on selective medium. Using scanning …

Ecological Indicator Development, Integration And Knowledge Mapping, Aaron Dean Peacock

Doctoral Dissertations

The overall goals of this project were: (1) to develop a microbiological ecological indicator that would describe military land disturbance, (2) integrate previously collected ecological indicator data from five separate research teams, and (3) produce knowledge maps with the resulting information that illustrates how the selected indicators are involved in ecosystem processes. To address goal one, soil samples were obtained from four levels of military traffic (reference, light, moderate, and heavy) with an additional set of samples taken from previously damaged areas. Using the soil microbial biomass and community composition as ecological indicators, reproducible changes showed increasing traffic disturbance decreases …

Structural Characterization Of Three Southeast Segments Of The Clark Fault, Salton Trough California, Benjamin E. Belgarde

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We examine the structural complexities of a 28-km long part of the Clark fault of the San Jacinto fault zone in southern California in order to better document its lateral extent and the style of deformation of its southeast end. Changes in structural style are observed as the Clark fault’s damage zone widens from ~ 1-2 km in crystalline rocks of the Peninsular Ranges southeastward to ~ 18 km in the sedimentary rocks of the San Felipe-Borrego subbasin of the Salton Trough. The Clark fault extends into the San Felipe-Borrego subbasin as the Arroyo Salada segment for ~ 11-12 km …

Quaternary Evolution Of The Colorado River At Lees Ferry, Arizona, William Scott Cragun

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A well-exposed suite of Colorado River fill terraces preserved at Lees Ferry records the oscillating history of this major river superimposed on its overall downcutting of the Colorado Plateau. Detailed mapping, sedimentology, cross-sectional surveys, and the use of two geochronometers have been used in order to establish a detailed chronostratigraphy for the area. Eight distinct deposits have been identified along the Colorado River (Ml -M7, and S3), and four deposits have been identified along the Paria River (Pl -P4).

Geochronology of six of these deposits using optically stimulated luminescence and cosmogenic ¹⁰Be exposure techniques indicates a long-term average bedrock …

Does The Southern Farmington Canyon Complex Record A Late Archean/Early Proterozoic Accretionary Complex?, Kyle C. Andreasen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Farmington Canyon Complex, situated along the Wasatch front in northern Utah, has been the target for many studies. The FCC has been interpreted to be a passive margin sedimentary wedge. Previous studies have yielded isotopic ages that broadly support an Archean age of formation, and a prominent mid-proterozoic amphibolite grade metamorphic event.

Based on this study, a new interpretation for the FCC is presented. Field relations and whole-rock geochemistry as well as recent advances in understanding Archean crustal processes have resulted in the FCC to be considered as an accretionary complex that formed along the SW margin of the …

Effects Of Quaternary Climate Change On Tributary Sedimentation And Geomorphology In Eastern Grand Canyon, Benjamin D. Dejong

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Climate variability has had a dramatic impact on eastern Grand Canyon tributaries over the past ~100 ky. This is readily observed in the Lava Chuar and Comanche catchments, which host well preserved colluvial remnants and river terraces that resulted from several climate-induced cycles of aggradation and incision. This study investigates these climate responses using surveying, sedimentology, and luminescence geochronology methods to investigate the mechanisms and timing of their deposition.

The survey data demonstrate that the concavity of terrace treads is lower than modern drainages. The sedimentology suggests the prevalence of stream-flow reworking of debris flow deposits and portrays an expected …

The Geologic History Of Subsurface Arkosic Sedimentary Rocks In The San Andreas Fault Observatory At Depth (Safod) Borehole, Central California, Sarah D. Draper

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The aim of the San Andreas Fault Observatory at Depth (SAFOD) project, a component of the NSF Earthscope Initiative, is to directly observe active fault processes at seismogenic depths through the drilling of a 3 km deep (true vertical depth) inclined borehole across San Andreas fault. Preliminary subsurface models based on surface mapping and geophysical data predicted different lithologies than were actually encountered. At 1920 meters measured depth (mmd), a sequence of well-indurated, interbedded arkosic conglomerates, sandstones, and siltstones was encountered. We present a detailed lithologic and structural characterization as a step toward understanding the complex geologic history of this …

The Marriage Of Eolian Rock Properties And Deformation Of The Nugget Formation; Anschutz Ranch East Field: Northeast Utah And Southwest Wyoming, Dustin J. Keele

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Nugget Formation in the Anschutz Ranch East field, northeast Utah and southwest Wyoming, provides an exceptional example of how primary eolian rock properties have a considerable influence on the style of structural deformation. Both new and existing subsurface data were integrated for an overall characterization of sedimentologic and diagenetic heterogeneities, which demonstrate relationships with different styles of structural compartmentalization in reservoirs. The Anschutz Ranch East field is a large asymmetric anticlinal trap in the Utah-Wyoming thrust belt. Three cores were analyzed in order to investigate brittle deformation in eolian facies: dune, apron, and interdune. Selected cores are located along …

Sequence Stratigraphy Of The Middle Cambrian Marjum Formation: Response Of Sedimentary Facies And Biota To Sea-Level Changes, Douglas D. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Research on the Marjum Formation provides insight into facies transitions in the House Range embayment of southwestern Utah during the Middle Cambrian. Sections of the Marjum Formation and equivalents were measured in strata representing shallow- (Drum Mountains), intermediate- (Wheeler Amphitheater), and deep-ramp (Marjum Pass) environments. This traverse across the embayment reveals strong litho- and biofacies changes. The Drum Mountains strata (343 m thick) are dominated by thick-bedded shallow-water limestone facies containing polymerid trilobites and stromatolites. The Wheeler Amphitheater locality (392 m thick) provides an example of intermediate deposits between deep-water and shallow-water environments and is characterized by limestone and subordinate …

Re-Evaluation Of The Jesse Ewing Canyon Formation: Implications For Neoproterozoic Paleogeography And Tectonic Setting Of Northeastern Utah, Andrew M. Brehm

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Detailed analysis of the basal unit of the Uinta Mountain Group, the Jesse Ewing Canyon Formation, of northeastern Utah and northwestern Colorado, expands on previous work by further documenting the character of the unit and proposing a revision of the description of the formation and interpretation. The Jesse Ewing Canyon Formation is ~≤1,000 meters thick as opposed to ≤225 meters thick, and the dominant lithology is not conglomerate, but rather finer-grained facies. The Jesse Ewing Canyon Formation reveals multiple alluvial fan point sources feeding a shallow body of water in an active rift basin at ~781 Ma.

Stratigraphic mapping, measured …

Discharge Monitoring, Chemical Characterization, And Source Identification Of Springs Along The East Side Of Southern Cache Valley, Utah, Aric Alan Olsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Discharge monitoring and water sampling of springs in the southeastern portion of Cache Valley, Utah was performed in order to determine recharge sources and the cause of decreasing flows for some springs. The discharges of 43 springs were measured monthly from May or June of 2005 through March of 2006. Water samples from 36 of these springs plus an additional 10 were analyzed for major ions and trace metals. Twenty-one of the springs were analyzed for deuterium and oxygen-18 and 10 of these were analyzed for tritium.

The springs were divided into groups based on when they had their peak …

Climatic And Structural Controls On The Geomorphology Of Wadi Sana, Highland Southern Yemen, Joshua Michael Anderson

USF Tampa Graduate Theses and Dissertations

Middle Holocene climate change forced significant environmental response and influenced human activities throughout southern Arabia. Climate models and proxy data indicate that climate along the southern Arabian peninsula changed from a moist phase, spanning the early to middle Holocene, to an arid phase, which persisted for the last ca. 5,000 years. A weakening and southward shift of the Southwest Indian Monsoon System, forced by northern hemisphere insolation variations in the precession band and/or glacial boundary conditions, is suggested as the mechanism for the abrupt shift to more arid conditions. Geoarchaeological evidence suggests that agriculture was more widespread and evolved alongside …

Influence Of Evapotranspiration On Patterns Of Ground-Water Conductivity In Small Basins, Ana Jiménez

USF Tampa Graduate Theses and Dissertations

Ground-water conductivity data were obtained from shallow wells in a 12 km2 stream-basin along a 400 m transect, extending from the divide to the stream. The stream, Pringle Branch, is a second-order perennial stream in Hillsborough County, Florida. The shallow stratigraphy consists of 2-3 m of fine sand over a layer of clayey silt and silty clay. Vegetation cover includes grasses on the upper and middle slope, and riparian woodlands on the foot slope and floodplain. Precipitation is about 1.3 m per year. Shallow ground-water conductivity is about 50 uS/cm at the divide. It increases moderately along the mid slope, …

Downstream Pathway Activation In Cultured Hepatocytes Following Treatment With Francisella Tularensis, Nicole Wakefield

Undergraduate Theses and Capstone Projects

Francisella tularensis, the intracellular pathogen that causes tularemia, was investigated to determine how it infects and replicates within mammalian hepatocytes. To date, it has been shown that hepatocytes can be infected by F. tularensis and that this causes considerable change in the protein phosphorylation state of several vital signaling molecules within the host cell. Protein kinase pathways can be mapped as signatures of infection. Hepatocytes tend to be susceptible to infection by F. tularensis, thus stimulating internal signaling. The Francisella strains used were selected with the goal of producing a model that can be used to elucidate the cell signaling …

Stratigraphy And Organic Carbon Contents Of Glacial Deposits In The City Of Portage, Michigan, U.S.A., Nathaniel A. Barnes

Masters Theses

The objectives of this study are to characterize the stratigraphy of the glacial drift in an area located in Portage, Michigan using four complete rotasonic cores, and to determine the variation of organic carbon content in the drift that may explain the high iron concentrations in the groundwater typically obtained in moderate to deep wells in southwestern Michigan. The four cores were characterized in detail in terms of lithology, textural and statistical analyses, gamma ray logging, S¹³C variation and organic carbon analyses. Clay minerals were characterized using X-ray diffraction analysis.

Results of this study identified two main diamicton …

Effects Of Elevated Atmospheric Co2 On Root Dynamics, Biomass And Architecture In A Scrub-Oak Ecosystem At Kennedy Space Center, Florida, Daniel Benjamin Stover

Biological Sciences Theses & Dissertations

A major gap in whole-plant ecology lies with our understanding of root system growth, function and distribution. Large belowground structures, in addition to fine roots, are of particular interest because of their role in carbon sequestration. Non-destructive methods, including ground-penetrating radar (GPR) and minirhizotron observation tubes, were used to investigate effects of elevated CO₂ on root biomass, dynamics (productivity, mortality, and turnover), root persistence and architecture in a fire dominated scrub-oak ecosystem. Open-top chambers have been exposed to elevated atmospheric CO₂ for the past eleven years at Kennedy Space Center, Florida. No significant sustained CO₂ treatment effects …

Seagrass-Mediated Carbonate Dissolution And Early Diagenesis In Bahamas Bank Sediments, Xinping Hu

OES Theses and Dissertations

This dissertation presents the results of studies examining the role that seagrasses play in carbonate dissolution and early diagenesis of Bahamas Bank sediments. Three aspects of this problem are addressed: (1) stable carbon isotopes as an indicator of early diagenesis of carbonates, using results of a field study; (2) carbonate dissolution stoichiometry and carbonate reprecipitation, using the results from closed-system sediment incubation studies; (3) carbonate dissolution and reprecipitation across the broader Bahamas Bank. In Chapter II, I examined δ¹³C in the dissolved inorganic carbon (DIC) of sediments with various degrees of seagrass densities. In low seagrass density and …

The Observation, Modeling, And Retrieval Of Bio-Optical Properties For Coastal Waters Of The Southern Chesapeake Bay, Xiaoju Pan

OES Theses and Dissertations

The primary purpose of this study was to develop an inverse method to retrieve the inherent optical properties (IOPs) and biogeochemical parameters (e.g. chlorophyll a concentration and salinity) appropriate to monitor the water quality and biogeochemical processes from remote sensing of the coastal waters in the southern Chesapeake Bay and coastal Mid-Atlantic Bight region (MAB) dominated by Case 2 waters. For this purpose, knowledge of the relationship between remote sensing reflectance (R_rs) and IOPs and the effect from bottom reflectance on R_rs, is required.

A substantial investigation of IOPs has been conducted for the coastal …

Late Pleistocene Climate Variability And Chemical Weathering In The Goriganga, Higher Central Himalaya, North India, Steven Paul Beukema

Dissertations

Relict lacustrine deposits in the Higher Central Himalaya, India, provide a rich repository of paleoclimate information for the period 16 ka to 11 ka. Stable isotope analysis of deposits near the village of Burfu shows the hydrologic balance between glacial meltwater and monsoon precipitation as source waters for the lake. During the period from 15.5 ka to 14 ka the Burfu lake was largely fed by melting glaciers. A warming event correlated to glacial Meltwater Pulse 1a indicates a sudden increase in carbonate weathering in the region accompanied by a gradual decrease in the ratio of glacial meltwater/monsoon precipitation feeding …

Geophysical Monitoring Probes And Their Applications To Some Hydrogeological Problems, Laura Smart

Dissertations

Geophysical monitoring probes were constructed to monitor the vertical changes of water content and ion concentration in the subsurface. These devices contain electrodes for resistivity measurements and thermistors for temperature measurements. They are designed to monitor the resistivity and temperature of the saturated zone, the transition zone, and the vadose zone near a groundwater/surface water interface. Additional installations at the site include four monitoring wells and four Time Domain Reflectometry (TDR) access tubes, each paired with the geophysical probe installations. Pole-Pole resistivity measurements with an a-spacing of 5 cm are made using a CR1000 Campbell Scientific, Inc. datalogger. Automated data …

Solute Chemistry And Isotopic Investigation Of The Groundwater Flow Paths In Honey Lake Basin, Lassen County, California And Washoe County, Nevada, Rachel M. Henderson

Theses and Dissertations

Honey Lake Basin is a large, hydrologically closed valley with two playa lakes that are separated by a low elevation sill. The Basin has a complex hydrogeologic setting, with numerous groundwater flow paths that interact with surface waters and three basic aquifers; shallow, deep, and geothermal. Thirteen flow paths; eleven cold and two thermal, are identified and the geochemical evolution of those paths are characterized by integrating solute chemistry and isotopic data. The chemical flow paths include recharge in either granitoid or volcanic terrains in the Sierra Nevada Range and the Modoc Plateau, respectively. The groundwater then flows through alluvial …

Pre-Historic Landslides On The Southeast Flank Of The Uinta Mountains, Utah: Character And Causes Of Slope Failure, Todd D. Bradfield

Theses and Dissertations

More than 100 landslides have been mapped along the southeast flank of the Uinta Mountains. Large landslide deposits are up to 4.6 kilometers long and have an area of approximately 5-9 km². Landslide types include multiple and successive rock slumps, debris slumps and debris flows. Most landslides have a main head scarp in the Bishop Conglomerate and the large landslides have many minor scarps. Multiple slump blocks are manifest by repeated transverse ridges and trenches in the head area of some landslides. Most body and toe areas are deeply incised by gully erosion (up to 91 meters deep) and drainages …

Structural Analysis Of Rock Canyon Near Provo, Utah, Laura Cardon Wald

Theses and Dissertations

A detailed structural study of Rock Canyon (near Provo, Utah) provides insight into Wasatch Range tectonics and fold-thrust belt kinematics. Excellent exposures along the E-W trending canyon allow the use of digital photography in conjunction with traditional field methods for a thorough analysis of Rock Canyon's structural features. Detailed photomontages and geometric and kinematic analyses of some structural features help to pinpoint deformation mechanisms active during the canyon's tectonic history. Large-scale images and these structural data are synthesized in a balanced cross section, which is used to reconstruct the structural evolution of this portion of the range. Projection of surficial …

The Origins Of Four Paterae Of Malea Planum, Mars, Susan K. Larson

Theses and Dissertations

Malea Planum is a volcanic plain on the southern rim of Hellas Planitia, the largest impact basin on Mars. Four large circular structures on Malea Planum have traditionally been identified as paterae, or low relief, central vent volcanoes (Plescia and Saunders, 1979). A geologic map was constructed and new crater counts made to explore the ages and origins of the paterae. Amphitrites and Peneus Paterae have radial patterns of wrinkle ridges on their flanks and distinct summit calderas (95 km and 130 km across) with arcuate bounding scarps. In contrast, Malea and Pityusa Paterae are broad depressions with diameters greater …

Stratification Of Southern Georgia Streams For Rapid Bioassessment Focusing On Differences In Structure And Function Of Black Water And Clear Water Streams, Salini Pradeep Pillai

Theses and Dissertations

As part of a rapid bioassessment project for the state of Georgia, relatively unimpaired reference streams and impaired sites were sampled for biological, chemical and physical parameters, and macroinvertebrates were identified. The metrics, biological, physical and chemical metrics, were selected using Ecological Data Application System Version 3.3.2k (EDAS). Discrimination efficiency and correlations were performed to determine the best metrics that separated impaired streams from reference streams and later on to form the index of stream water quality. Principal components analysis of the selected metrics showed that some of the blackwater reference streams and clearwater reference streams are randomly placed over …