Thèses : « Eastern North American margin »

1

Lynner, Colton, et Robert W. Porritt. « Crustal structure across the eastern North American margin from ambient noise tomography ». AMER GEOPHYSICAL UNION, 2017. http://hdl.handle.net/10150/625356.

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Passive tectonic margins, like the eastern North American margin (ENAM), represent the meeting of oceanic and continental material where no active deformation is occurring. The recent ENAM Community Seismic Experiment provides an opportunity to examine the crustal structure across the ENAM owing to the simultaneous deployment of offshore and onshore seismic instrumentation. Using Rayleigh wave phase and group velocities derived from ambient noise data, we invert for shear velocity across the ENAM. We observe a region of transitional crustal thicknesses that connects the oceanic and continental crusts. Associated with the transitional crust is a localized positive gravitational anomaly. Farther east, the East Coast magnetic anomaly (ECMA) is located at the intersection of the transitional and oceanic crusts. We propose that underplating of dense magmatic material along the bottom of the transitional crust is responsible for the gravitational anomaly and that the ECMA demarks the location of initial oceanic crustal formation.

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2

Cornell, Sean Richard. « The Last Stand of the Great American Carbonate Bank : Tectonic Activation of the Upper Ordovician Passive Margin in Eastern North America ». Cincinnati, Ohio : University of Cincinnati, 2008. http://rave.ohiolink.edu/etdc/view.cgi?acc_num=ucin1226880226.

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Thesis (Ph.D.)--University of Cincinnati, 2008.
Advisor: Dr. Carlton Brett PhD (Advisor), Dr. Warren Huff PhD (Committee Member), Dr. J.B. Maynard PhD (Committee Member), Dr. Thomas Algeo PhD (Committee Member), Dr. Brian Witzke PhD (Committee Member), Dr. Kees Dejong PhD (Committee Member). Title from electronic thesis title page (viewed Feb. 3, 2009). Keywords: sequence stratigraphy; ordovician; taconic orogeny; blountian tectophase; chemostratigraphy; strontium isotopes; time restricted facies; mohawkian; trenton group; black river group; chazy group. Includes abstract. Includes bibliographical references.

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Leatham, W. Britt. « Conodont-based chronostratigraphy and conodont distribution across the Upper Ordovician western North American carbonate platform in the eastern Great Basin and a model for Ordovician-Silurian Genesis of the platform margin based ... / ». The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487332636474718.

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4

Speer, William D. « Systematics of Eastern North American Bracken Fern ». Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36715.

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The cosmopolitan Pteridium aquilinum (L.) Kuhn is widespread throughout eastern North American, where it is represented primarily by Tryon's (1941) var. latiusculum (Desv.) Underw. and var. pseudocaudatum (Clute) Heller. The taxonomy of Pteridium is controversial. Fourteen isozyme loci and 12 morphological characters were used to assess the taxonomic relationship of these two varieties. Isozyme data indicated a high mean genetic identity (I = 0.976) between eleven bracken populations. Strong patterns of geographic variation for isozyme allele frequencies were also observed. The isozyme results did not separate the two taxa. Numerical analysis of the morphology distinguished the two taxa when the qualitative characters were used alone or in conjunction with some of the quantitative traits. All qualitative characters differed significantly between the two taxa. No perceptible geographic pattern of variation was observed. Morphological distinctiveness was maintained even in those localities where both taxa were present, with few or no intermediates being found. Isozyme evidence suggestive of gene flow between the two varieties was found at Greensboro, NC, where the two morphotypes were easily recognizable. The isozyme evidence strongly indicates conspecificity, while the morphological evidence supports their status at the varietal level.
Master of Science

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5

Rodger, Matthew. « A marine geophysical study of the Amazon continental margin, North-Eastern Brazil ». Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.504519.

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6

Francavilla, Stephen A. « Millennial-scale variability in denitrification and phosphorus burial in the Eastern Tropical North Pacific ». Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/3860.

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The remarkable synchrony between changes in temperature recorded in Greenland ice cores and variations in N isotope records from sedimentary cores recovered from the Arabian Sea and the Eastern Tropical North Pacific (ETNP) has provided evidence for teleconnections between changes in marine denitrification in the tropics and climate variations in the northern high latitudes. Changes in tropical denitrification have been attributed to changes in productivity, changes in the source of intermediate waters and the flux of dissolved oxygen to suboxic zones. Variations in marine denitrification and anammox occurring at intermediate depths in proximity to productive continental margins have had profound effects on the N:P ratio of upwelled waters between stadials and interstadials, and may have indirectly affected carbon sequestration in the ocean by changing the balance of nutrients available to primary productivity. Competitive equilibrium, the changing stoichiometric balance of elements available as nutrients and the shorter residence time of N compared to P are factors that are believed to favour diazotrophs (N2-fixing organisms) during interstadials and shift the competitive advantage to non-N2-fixing ecosystems during stadials. This study presents a very high-resolution analysis of sedimentary nitrogen isotope records, phosphorus concentrations and bulk detrital element concentrations from two cores collected along the Pacific Mexican Margin. The results show that the oxygen minimum zone (OMZ) bathing intermediate waters in ETNP is modulated by the interaction of a Northern Hemisphere climate component with the “leakage” of heavy nitrate believed to derive from the Eastern South Pacific (ESP). This southerly component has a more “Antarctic” timing and is similar to records from the Peru-Chile margin. The sedimentary core recovered from the Mazatlan margin shows a “Greenland” timing of millennial-scale events, with reduced upwelling and reduced primary productivity, a less intense OMZ leading to reduced denitrification and a more southerly position of the mid-tropospheric subtropical ridge during stadials. This would have increased the onshore flow of moist air, ultimately leading to increased precipitation along the western Mexican Margin. Interstadials show a reversal of these conditions. In contrast to the Mazatlan core, the N isotope record from the core recovered from the Gulf of Tehuantepec records an element of “Antarctic” timing superimposed on local, millennial-scale variations in denitrification that are more similar in timing to Greenland temperature changes. In addition, the interpretation of observed variations in detrital elements from the Gulf of Tehuantepec highlights latitudinal displacements of the ITCZ that are consistent with those observed in the Cariaco Basin in Venezuela. Bulk P concentrations from both cores suggest that although phosphorite formation in the ETNP during interstadials is not as widespread as previously thought, the very high accumulation rates in the Gulf of Tehuantepec and Mazatlan Margin lead to total Holocene phosphorus burial rates that are up to 4-5 times higher than had been estimated in previous studies. These observations lead to the argument that the ETNP may play a more important role in regulating global P budgets than was previously thought and call for an improved appreciation of the benthic microbial communities that modulate biomes at tropical latitudes.

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7

Nameroff, Tamara J. « Suboxic trace metal geochemistry and paleo-record in continental margin sediments of the eastern tropical North Pacific / ». Thesis, Connect to this title online ; UW restricted, 1996. http://hdl.handle.net/1773/8514.

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8

Allin, Joshua Reg. « The timing and frequency of large-volume submarine landslides and turbidity currents along the north-eastern Atlantic Margin ». Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/407493/.

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Submarine landslides and turbidity currents are one of the most voluminous sediment transport mechanisms operating on our planet. Due to their potential size (>100 km3) and speed (>20 m/s) they pose considerable risk to coastal settlements and strategic marine infrastructure. This thesis aims to investigate the processes that precondition and trigger submarine landslides and turbidity currents within submarine canyons and on open continental slopes. Sediment cores, age models, and statistical analyses are used initially to test the effects of eustatic sea level on the recurrence rates of turbidity currents that fill and flush the Nazaré Canyon. Recurrence rates of turbidity currents that fill the canyon are strongly influenced by eustatic sea level, while more infrequent flows that flush the canyon are only associated with shifts in eustatic sea level periodicity and amplitude. The form of the frequency distribution of canyon filling and flushing turbidity currents also differ markedly, suggesting they have different triggers. This thesis also aims to understand the geohazard implications of large submarine landslides. The Trænadjupet Slide is a large ( > 400 km3) submarine landslide that occurred approximately 4,000 years ago on the Norwegian Margin. Unlike some other large submarine landslides, the Trænadjupet Slide did not trigger a widespread tsunami based on available coastal studies. The age of the Trænadjupet Slide is refined here to between ~2,600 and ~3,400 cal BP. The absence of a widespread tsunami associated with the Trænadjupet Slide may be explained by its emplacement dynamics (e.g. speed, acceleration, or time gaps between stages of failure). These findings have importance for landslide geohazards in the North Atlantic, as they suggest that other similarly-sized slides on the Norwegian Margin or elsewhere may not have produced very damaging tsunamis.

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Haines, Helen Rozeann. « Intra-site obsidian distribution and consumption patterns in Northern Belize and the North-Eastern Peten ». Thesis, University College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325664.

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10

Lowe, Charles H., R. Roy Johnson et Peter S. Bennett. « Riparianlands are Wetlands : The Problem of Applying Eastern American Concepts and Criteria to Environments in the North American Southwest ». Arizona-Nevada Academy of Science, 1986. http://hdl.handle.net/10150/296391.

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From the Proceedings of the 1986 Meetings of the Arizona Section - American Water Resources Association, Hydrology Section - Arizona-Nevada Academy of Science and the Arizona Hydrological Society - April 19, 1986, Glendale Community College, Glendale, Arizona

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11

Labat, Sean J. « The Holy Eastern Orthodox Catholic and Apostolic Church in North America, 1927-1934 a case study in North American missions / ». Theological Research Exchange Network (TREN), 1995. http://www.tren.com.

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12

McIntyre, Shona Helen. « Morphological and biochemical variability within eastern North American populations of Asterionella Hassall, possible taxonomic implications ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq21412.pdf.

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13

Wells, Jennifer. « The Black Freedom Struggle and Civil Rights Labor Organizing in the Piedmont and Eastern North Carolina Tobacco Industry ». Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4790.

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This thesis examines labor organizing in the U.S. South, specifically the Piedmont and eastern regions of North Carolina in the mid-twentieth century. It aims to uncover an often overlooked local history of civil rights labor organizing which challenged the southern status quo before America's 'mainstream' civil rights era of the 1950s and 1960s. This study argues that through labor organizing, African American tobacco workers challenged the class, gender, and race hierarchy of North Carolina's very profitable tobacco industry during the first half of the twentieth century. In doing so, the thesis contributes to the historiography of black working class protest, and the ever-expanding field of local civil rights histories and the long civil rights movement.

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14

Stokes, Richard L. « Pollination Ecology, Self-incompatibility and Genetic Diversity in the Herbaceous Eastern North American Spring Ephemeral, Erythronium americanum ». University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1353089025.

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15

Eilers, Linda. « When Calvinist and Arminian beliefs collide facilitating communication between North American professors and Russian Bible students / ». Theological Research Exchange Network (TREN), 1998. http://www.tren.com.

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16

Morris, Ashley Brigham. « Multi-pronged approach to eastern North American biogeography : phylogeny, phylogeography, and predictive modeling of temperate woody plant species / ». View online, 2006. http://etd.fcla.edu/UF/UFE0017365/morris_a.pdf.

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17

Alshabani, Nuha. « EXPLORING THE LIVED EXPERIENCE OF TRANSMITTING RESILIENCY AMONG ARAB, MIDDLE EASTERN, AND NORTH AFRICAN (AMENA) MIGRANTS ». University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1625581685665257.

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18

Makhlouf, Issa Mohamed. « The stratigraphy and sedimentation of Upper Cambrian, Permo- Triassic and Lower Triassic rocks along the North Eastern margin of the Dead Sea basin, Jordan ». Thesis, University of Newcastle Upon Tyne, 1987. http://hdl.handle.net/10443/552.

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A thick sequence of predominantly terrigenous clastic sediments ranging from Cambrian to Cretaceous in age is exposed along-the northeastern margin of the Dead Sea, Jordan. The present study is confined to rocks of Upper Cambrian, Permo - Triassic (Um Irna Formation)-and Lower Triassic (Ma'in Formation) age, -which attain a total thickness of about 150 m. The lithology, stratigraphy, sedimentary structures, lithofacies and depositional environments of these sediments have been studied in detail. Early After deposition of the'Middle Cambrian marine Burj Formation, a major regressive event occured punctuated by minor transgressive phases, during which the Upper Cambrian sediments were laid down. These lie conformably on the Burj Formation, and are unconformably overlain by the Permo - Triassic Um Irna Formation. The Upper Cambrian succession consists of a medium - to coarse - grained quartzarenite facies and a subordinate heterolithic facies of siltstone and mudstone with sandy lenses. Internally the arenites are structured by trough cross - bedding arranged in cosets or solitary sets. Foreset dip directions show a unidirectional northwesterly mode. Most of the trough cross - beds are deformed giving rise to penecontemporaneous overturning of the foresets in the down-current direction. This is attributed to shear stress exerted by a dense sediment - laden current of water moving over the top of seismically liquefied cross - bedded sand. The Upper Cambrian sediments were, deposited on a braidplain and adjacent tidal flats due to periodic shifting of the active part of the braidplain. Reworking of the inactive part of the braidplain by tidal currents and subsidence led to marine incursions and the devel - opment of tidal flats. The Permo - Triassic Um Irna Formation is conformably overlain by interbedded sandstone, siltstone and mudstone of the Lower Triassic Ma in Formation. Um Irna Formation can be divided into a lower and upper member according to grain size and the proportion of sandstone to siltstone and shale in succession. The lower member attains a thickness of 10 m and is characterised by the presence of five sandstone-dominated fining - upward sequences from 0.75 to 2.15 m thick comprising an erosively - based coarse-to fine-grained sandstone overlain by, and laterally intertonguing with, maroon silt - stone and shale. The sandstones are internally structured by small - scale (< 20 cm thick) trough cross - bedding. Foreset azimuths show a unidirectional trend towards the north - northwest. The upper member also consists of five fining - upward sequences from .4 to 14.5 m thick, each sequence comprising an erosively - based pebbly sandstone grading up through medium-and fine-grained sandstone into maroon siltstone and silty - shale. Trough cross - bedding is the dominant internal structure with foresets directed towards the north - northwest. A characteristic feature of the silty - shale is the presence of abundant ferruginous concretions (pisoliths). Both members were deposited by fluvial processes. The lower member is attributed to deposition mainly by shallow, low sinuosity sand bed channels draining the distal reaches of a low gradient alluvial plain. The upper member contains a higher proportion of overbank fines (silt and mud) consistent with deposition by a mean - dering fluvial system, while the dominance of pebbly components in the sandy facies and their multilateral and multistorey nature suggests deposition by low sinuosity channels on the more proximal reaches of the braidplain. The nature of the concretions (Fe- pisoliths)- suggests that the diagenetic (pedogenic) environment was complex with alternating episodes of leaching, cementation and fracturing during their growth. The Lower Triassic Ma'in Formation is overlain by the shallow marine Dardur Formation. Two facies are recognised within the Ma'in Formation. The lower Himara Member comprises two facies which are deep maroon in colour and highly bioturbated: a lower sandy facies and an upper heterolithic facies (sand, silt and mud). This member is thought to have been deposited on a-tidal flat as evidenced by rhythmic beds of sand, silt and clay, flaser, wavy and lenticular bedding, herringbone cross - bedding, mudcracks, raindrop imprints, superimposed ripple marks showing interference, and ladder back forms reflecting shallowing and late stage emergence run off features. The depositional model proposed is one of a microtidal to mesotidal coastline, with a palaeotidal range of 0.45 m to 2.35 m. The coastline is inferred to have been interacting with a braided fluvial plain, which fed in quartzitic sediment from the southeast as indicated by the palaeocurrent pattern. The upper, more sandy, Nimra Member is cream in colour, more fossiliferous and more calcareous. The proposed depositional model is that of a shallow subtidal shelf receiving clastic sediment by way of river mouths extending seawards as subtidal channels. The shallow open marine nature of the environment is indicated by the presence of oold'si ,foraminifers, lamellibranchs, echinoids, bryozoars and gastropod fragments cemented mainly by dolomite. The overall model proposed for the Ma'in Formation is that of an intertidal flat (Hirnara Member) located between a braided alluvial plain (Um Irna Formation) and a subtidal marine shelf (Nimra Member).

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19

Slattery, Mico T. « Towards a comparative study of the concept of mind/consciousness in Western science, Eastern mysticism and American Indian thought ». Diss., Connect to online resource - MSU authorized users, 2008.

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20

Nykiel, Anthony J. « The geology, petrology, and geochemistry of the area north of Spriggs Creek Bore, western margin of the Entia Dome, Harts Range, Eastern Arunta block, Northern Territory / ». Title page, table of contents and abstract only, 1986. http://web4.library.adelaide.edu.au/theses/09SB/09sbn995.pdf.

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21

Smeilus, Sarah E. « Effects of stock origin on the growth and survival of the eastern oyster, Crassostrea virginica, in southeastern North Carolina / ». Electronic version (Miscrosoft Word), 2006. http://dl.uncw.edu/etd/2006/smeiluss/sarahsmeilus.doc.

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22

Weiland, Andrew W. « Marshelder (Iva annua L.) Seed Morphology and Patterns of Domestication in Eastern North America ». The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1365684474.

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23

Hildebrandt, Frank A. « Effective evaluation a required variable for the revitalization of plateaued churches in the Eastern Association of the North American Baptist Conference / ». Theological Research Exchange Network (TREN), 1997. http://www.tren.com.

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24

Walsh, Kevin B. Jr. « GEOCHRONOLOGICAL AND GEOCHEMICAL CONSTRAINTS ON THE ORIGIN OF THE CARTOOGECHAYE TERRANE, WESTERN NORTH CAROLINA : IMPLICATIONS FOR THE LATE PRECAMBRIAN TO EARLY PALEOZOIC EVOLUTION OF THE EASTERN LAURENTIAN MARGIN ». UKnowledge, 2018. https://uknowledge.uky.edu/ees_etds/57.

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The Cartoogechaye terrane (CT) is an enigmatic migmatite terrane within the Central Blue Ridge province of the southern Appalachians. Previous work identified exotic Pb isotope compositions within the CT (Quinn, 2012). More recent studies that mapped the extent of potentially exotic metaigneous lithologies yield U-Pb zircon ages consistent with a native Laurentian margin metasedimentary origin (Larkin, 2016). This study focused on the possible extent of similar lithologies in the Clyde quadrangle and provides further constraints on the crustal affinity of the CT. The Clyde quadrangle consists of four distinct lithologic packages: the CT, Ashe metamorphic suite, Great Smoky Group, and Grenville basement. Five samples within the Clyde quadrangle and one sample from Wayah Bald quadrangle were collected for detrital zircon (DZ) U-Pb geochronology and whole rock geochemistry for comparison similar anlayses from other bedrock units in the region. Dominant DZ age modes consist of the Grenville doublet (1050 Ma and 1150 Ma) or a modified version of it. Minor age modes exist at ~450 Ma, 600-750 Ma, and 1300-1550 Ma. Zircons for all but one sample display heterogeneous external and internal cathodoluminescence morphologies, consistent with a sedimentary protolith for the paragneisses. Whole rock compositions are consistent with weathering of and derivation from a local basement source. U-Pb age data are most consistent with an eastern Laurentian sedimentary provenance for five samples. The presence of 450-460 Ma grains is most consistent with high-grade Taconian regional metamorphism. The lack of a major Shawinigan age mode and zircon morphology for ca. 980-1050 Ma metamorphic zircons indicate that sample CLY16-1 is a syn-orogenic metasediment within the Grenville basement underlying the CT.

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25

Hodges, Orlice Clayton. « Examining a Sense of Belonging| African-American High School Equivalency Students Pursuing a Higher Education at a Small Rural Community College in Eastern North Carolina ». Thesis, Wingate University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10643012.

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This study examines relationships of African-American high school equivalency (HSE) students' sense of belonging to their peers, faculty, and community college environment. A sense of belonging is an important factor in understanding students’ internal and external motivations, perceptions, desires, and academic successes. For many African-American HSE students, community colleges are the pathways chosen to enhance their skills for a better education, potential income increase, and possible advancement in the workforce. A sense of belonging, socioeconomic desires, and cultural influences can promote adult learners’ return to the classroom in pursuit of a high school diploma. The purpose of this study was to examine and gain in-sight on a sense of belonging, educational attainment, and gender gaps of African-American high school equivalency female and male students’ experiences in quest of a higher education. This mixed-method research study recorded students’ shared experiences and insight in regards to a sense of belonging; as a result, the findings from this study have implications to change policy, curriculum, and program structure. The significance of this study was to make a contribution to the knowledge on African-American students’ sense of belonging with peers, faculty, and the community college environment.

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Royce, Karen Louise. « Geophysical Investigation of an Early Late Woodland Community in the Middle Ohio River Valley : The Water Plant Site ». The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1313416567.

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Cass, Christine J. « A Comparative Study of Eucalanoid Copepods Residing in Different Oxygen Environments in the Eastern Tropical North Pacific : An Emphasis on Physiology and Biochemistry ». Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3036.

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The eastern tropical north Pacific (ETNP) is characterized by one of the ocean's most severe midwater oxygen minimum zones (OMZs), where oxygen levels are often less than 5 µM. The copepod family Eucalanidae is a numerically abundant and diverse zooplankton group in the ETNP, and displays a wide range of vertical distributions related to environmental oxygen concentrations. The goal of this dissertation was to develop a better understanding of the ecology, physiology, and biochemistry of closely related copepod species (family Eucalanidae) that inhabit the ETNP OMZ system. This was accomplished through examining different parameters relating to (1) metabolic rates, (2) detailed lipid composition and biomarkers, and (3) body composition, enzyme activity and survivorship in low oxygen water. Oxygen consumption, ammonium, urea, and phosphate excretion rates were generally highest in Subeucalanus subtenuis, a copepod primarily residing in the upper euphotic zone. Eucalanus inermis, typically found in the lowest oxygen environment of the species examined, showed significantly lower metabolic rates largely due to high water content. Rhincalanus rostrifrons, residing primarily in the upper oxycline, showed intermediate rates, likely relating to its higher reliance on lipid catabolism than S. subtenuis and E. inermis. Urea excretion rates showed a complicated relationship with temperature and oxygen, which calls for further study. Knowledge of such interactions is necessary for accurate modeling of nitrogen cycles in OMZ and other oceanic regions. Lipid biomarkers suggested that S. subtenuis, E. inermis and Pareucalanus attenuatus all fed primarily on particulates near the chlorophyll maximum region, while R. rostrifrons and R. nasutus likely fed on sinking particulates at depth. These results also emphasized the difference in lipid composition between wax esters and triacylglycerol components of storage lipids. This study suggested a much larger role of phylogeny in characterizing lipid contents than previously thought. Body composition, enzyme assays and survivorship studies suggested that E. inermis, S. subtenuis, P. attenuatus, R. nasutus and R. rostrifrons formed four separate ecological groups based on genus. E. inermis had low organic matter, moderate lactate dehydrogenase (LDH) activity, and high survivorship at oxygen concentrations < 20 µM. Rhincalanus spp. also had moderate LDH activity and high survivorship in low oxygen, but were unique in particularly low protein and high lipid content. S. subtenuis was characterized by high protein content, no measurable LDH activity and low survivorship in < 20 µM O2. P. attenuatus was similar to S. subtenuis in many respects, but had lower protein content and a different lipid accumulation strategy. In conclusion, eucalanoid copepods utilized many different ecological strategies in the ETNP OMZ system. Features of different ecological groups fit well with their observed vertical distributions in the water column. Understanding the ecology of organisms in OMZ systems will allow us better predictive capability for the effects of expanding OMZs in other regions.

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Verdel, Charles Steven Eiler John Eiler John. « I. Cenozoic geology of Iran : an integrated study of extensional tectonics and related volcanism. II. Ediacaran stratigraphy of the North American cordillera : new observations from eastern California and northern Utah / ». Diss., Pasadena, Calif. : California Institute of Technology, 2009. http://resolver.caltech.edu/CaltechETD:etd-09182008-092505.

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Mechehoud, Meriem. « U.S. Cultural Diplomacy in the Middle East and North Africa : The Impact of the MEPI Program on Youth Political Involvement and Civic Engagement ». Bowling Green State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1471615317.

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Allison, Benjamin V. « Through the Cracks of Detente : US Policy, the Steadfastness and Confrontation Front, and the Coming of the Second Cold War, 1977–1984 ». Kent State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=kent1587394697039162.

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31

Gaolaolwe, Dikabelo. « The nature of the legal relationship between the three RECs and the envisaged TFTA : a focus on the dispute settlement mechanism ». Thesis, University of the Western Cape, 2013. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_4433_1380708981.

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Kinney, Sean Thomas. « Re-evaluating the timescale of rift and post-rift magmatism on the Eastern North American Margin via zircon U-Pb geochronology ». Thesis, 2021. https://doi.org/10.7916/d8-hwtn-b231.

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The modern plate tectonic paradigm provides a predictive model to understand what mediates dynamic processes at both plate margins and intraplate settings. At some locations on the Earth, the geological record provides evidence of apparent violations of this theoretical framework. In this dissertation, I examine a region on the rifted continental margin of Eastern North America, where at least four distinct episodes of magmatism occurred (in the Late Triassic, Early Jurassic, Early Cretaceous) since the onset of rifting and ultimate breakup of the supercontinent Pangea. It also coincides with a present-day low seismic velocity anomaly in the upper mantle. No other region on the Eastern North American Margin has a record of such anomalous dynamic processes occurring and persisting for more than 200 Myr. In this dissertation, I primarily use zircon U-Pb geochronology to establish the basic chronological framework in which magmatic and magmatic-hydrothermal systems in this region existed and persisted, establishing the temporal parameter space in which it will be possible to test geodynamic mechanisms for their formation. In Chapter 2, I use ultra-high precision zircon U-Pb geochronology via Chemical Abrasion-Isotope Dilution-Thermal Ionization Mass Spectrometry (CA-ID-TIMS) to test whether the onset of magmatism in the largest igneous body in this region (the White Mountain Batholith) is linked to the eruption of the vast flood basalts within the Central Atlantic Magmatic Province (CAMP) and whether its apparent duration is indeed > 50 Myr, as previous workers using whole rock K-Ar and mineral Ar-Ar geochronologic methods suggest. My work uncovered a previously unknown episode of rift-related magmatism in the region that precedes the both the CAMP and the emplacement of the White Mountain Batholith by 3 – 5 Myr. In Chapter 3, I use a combination of high-precision zircon U-Pb geochronology and absolute plate motion models to test whether the Cretaceous igneous province in this region resulted from hot spot magmatism as North America moved over the purported Great Meteor Hotspot. These results cannot falsify the hotspot hypothesis and the new zircon U-Pb ages therefore provide the best available chronological constraints for one of the longest-lived hot spot tracks on the Earth. In Chapter 4, motivated by the confirmation of age discrepancies between low- and intermediate-temperature chronometers and the zircon U-Pb ages presented in Chapter 2, I use a combination of both CA-ID-TIMS and LA-ICP-MS zircon U-Pb geochronologic techniques to place constraints on the timing and duration of magmatism for the Late Triassic-Early Jurassic province. The results of this chapter demonstrate that the magmatism of the White Mountain Magma Series occurs in discrete pulses through much of the Jurassic. Together with zircon Hf isotopic analyses from select samples, I synthesize these age results and construct a hypothesis testing framework in which it will be possible for future investigators to unravel the geodynamic complexities in this region. I provide recommendations for future work and emphasize the need for unified approaches coupling geochronology, geochemistry, and geophysics, to test the range of possible mechanisms responsible for these episodes of anomalous tectono-magmatic activity.

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Eddy, Drew Richard. « Mesozoic rifting along the eastern seaboard of North America : insights from the seismic velocity structure of the Newfoundland margin and the northern Gulf of Mexico ». Thesis, 2014. http://hdl.handle.net/2152/28403.

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Passive margins along the eastern seaboard of North America formed during early Mesozoic continental rifting and seafloor spreading, tectonic processes that are not fully understood. Seismic refraction and reflection data at the northeastern and north-central Gulf of Mexico and the Grand Banks of Newfoundland, Canada, are used to interpret the deep seismic velocity structure of sediments, crust, and mantle. These interpretations allow for a better understanding of continental rifting, mantle upwelling, magmatism, and seafloor spreading. Magma-poor rifting of the Newfoundland-Iberian margin developed a wide continent-ocean transition zone (COT). I present an analysis of 2-D marine seismic refraction and reflection data from the SCREECH project, including a shear velocity model to constrain the composition of the Newfoundland COT. Comparing SCREECH Line 2 Vp/Vs ratios with depth to potential lithologies supports a COT comprised of hyperextended continental crust and serpentinized mantle. Reconstructions of the opening of the Gulf of Mexico basin are impeded by a lack of seafloor magnetic anomalies and an abundance of sediments that obscure acquisition of seismic refraction datasets. Accordingly, the roles of mantle upwelling, magmatism, and lithospheric extension in this small ocean basin are poorly known. I present new 2-D marine seismic refraction data from the U.S. Gulf of Mexico collected during the 2010 GUMBO project. Rifting in the eastern Gulf of Mexico developed above a zone of anomalously high mantle potential temperatures that led to abundant magmatism. Syn-rift basins in continental crust, high velocity lower crust, a narrow zone of crustal thinning, and seaward-dipping reflectors support this interpretation. Oceanic crust here is thick despite slow seafloor-spreading rates, implying continuation of a thermal anomaly after rifting. In the north-central Gulf of Mexico, transitional crust is consistently thin (~10 km) across a wide zone. Velocity-depth comparisons, asymmetry of the north-central Gulf with the Yucatán margin, and dating of onshore xenoliths support either stretched and magmatically intruded continental crust or a multi-stage episode of seafloor spreading with ridge jumps. I contend that although tectonic inheritance may ultimately influence the location of a passive margin, the rifting process is largely controlled by mantle potential temperature and upwelling rate.
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English, Joseph M. « Convergent margin tectonics in the North American Cordillera : implications for continental growth and orogeny ». 2004. http://hdl.handle.net/1828/391.

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Continental growth may be accomplished at active convergent margins through tectonic accretion and orogeny. Accretionary processes believed to add material to continents include the collision of island arcs and other unsubductable crustal blocks. Using the Intermontane belt as a case study for assessing accretionary processes, it is concluded that island-arc collision and accretion was the principal mechanism for continental growth with relatively minor contributions from 'sliced-off oceanic seamounts and/or plateaux. Fold and thrust belt formation in the northern Intermontane belt records a Middle Jurassic orogenic event that can be attributed to the collision of island-arc highlighting the importance of island-arc collision for causing orogenesis in the North American Cordillera. However, not all orogenic events in the North American Cordillera can be readily attributed to a collisional event. The leading model for driving Laramide orogenesis in the United States is flat-slab subduction, and thermal modelling indicates that subduction of a relatively buoyant oceanic plateau/aseismic ridge may have been responsible for the shallow trajectory. In the Canadian and Mexican portions of the Laramide, the coeval development of a magmatic arc within 300 km of the trench refutes the existence of flat-slab subduction in these regions, and therefore the processes responsible for this orogeny remain enigmatic and require resolution.

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Sabin, Joel Sean. « Investigating eastern North American tree species richness and diversity using relevé data ». 2005. http://purl.galileo.usg.edu/uga%5Fetd/sabin%5Fjoel%5Fs%5F200505%5Fms.

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Carter, Brad T. « Geologic investigations in the Smith River Allochthon and Lynchburg Group, southern Appalachians : implications for the evolution of the eastern Laurentian Margin / ». 2006. http://www.lib.ncsu.edu/theses/available/etd-03202006-145445/unrestricted/etd.pdf.

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Stefl, David J. « Snowfall variability in the eastern United States associated with the North Atlantic Oscillation, Pacific-North American, and El Niño/Southern Oscillation teleconnection patterns ». 2014. http://cardinalscholar.bsu.edu/handle/123456789/198496.

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Teleconnection patterns wield a strong influence on regional climate variability. Several studies have linked North American hydroclimatology with the teleconnection strength and phase. The purpose of this study is to understand the spatiotemporal relationship between three large-scale modes of atmospheric variability and snowfall distributions in the eastern United States. In particular, snowfall responses were examined on a sub-regional level to the Pacific-North American (PNA), North Atlantic Oscillation (NAO), and El Niño/Southern Oscillation (ENSO) patterns at different periods through the winter season using a similar methodology found in Smith and O’Brien (2001). Snowfall data were collected from the United States Historical Climatology Network (USHCN) for the years 1951-2012. In order to examine snowfall within season variability, each snowfall season was grouped into three, three-month overlapping periods: early, October, November, and December (OND); middle, December, January, and February (DJF); and late, February, March, and April (FMA). Average monthly teleconnection pattern index values for PNA, NAO, and ENSO were collected from the Climate Prediction Center (CPC) and National Climatic Data Center (NCDC) and averaged into corresponding periods. For each station, boxplots were created showing the winter snowfall range as well as the first, second (median), and third quartiles. An observational analysis was performed in which the station boxplots were then grouped according to one of three general median snowfall teleconnection pattern responses (e.g., high median snowfall in NAO negative phase). A non-parametric two sample t-test was employed to determine if the shifts in median snowfall between teleconnection pattern phases are statistically significant. The results of the statistical analysis revealed that although there were observable shifts in snowfall in relation to teleconnection pattern phase, the observed shift was not significant in an appreciable amount of stations.

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« Middle Eastern and North African (MENA) American Youth Reports of their Parenting Experiences : Associations with Mental and Physical Health ». Doctoral diss., 2019. http://hdl.handle.net/2286/R.I.53748.

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abstract: Scant research examines the associations between parenting behaviors and the psychological health of Middle Eastern and North African (MENA) American youth. Developmental research consistently demonstrates that an authoritarian parenting style (often characterized by rejecting and controlling behaviors, and a common style among MENA parents) is maladaptive for offspring health; however, no study has empirically tested the associations of these behaviors from mothers and fathers with the health of MENA American youth. Using survey data from 314 MENA American young adults (Mage = 20 years, range 18 – 25 years, 56% female), the current study tested the associations between commonly studied parenting behaviors - acceptance, rejection, harsh parenting, and control - with the mental (stress, depression, and anxiety) and physical health (general health perceptions, pain, and somatization) of MENA American youth. Confirmatory factor analysis tested new items informed by preliminary focus groups with original items from the Child Report Parenting Behavior Inventory (CRPBI) to create culturally-informed parenting factors. Results indicated that youth-reported higher maternal acceptance was associated with fewer mental health symptoms, higher maternal harsh parenting with higher mental health symptoms, and higher maternal rejection with worse physical health; father rejection was associated with higher mental health symptoms and worse physical health. Further, the associations between parenting and physical health were moderated by youth Arabic orientation, such that those with higher Arabic orientation showed the best physical health at higher levels of acceptance, and the worst physical health at higher levels of rejection, harsh parenting, and control. Associations between parenting and health did not differ by youth gender. The current findings suggest cross-cultural similarities in the beneficial functions of parental acceptance, and detrimental functions of parental rejection and harsh parenting, with MENA American youth. The associations between parenting and health were exacerbated, for better or for worse, for more Arabic-oriented youth, suggesting these youth may be more greatly impacted by perceptions of their parents’ behaviors. Findings have implications for family interventions working with MENA populations.
Dissertation/Thesis
Doctoral Dissertation Psychology 2019

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Thomson, Ashley. « Phylogeography, introgression, and population structure of the eastern North American birches Betula alleghaniensis, B. papyrifera, and B. lenta ». Thesis, 2013. http://spectrum.library.concordia.ca/977473/1/Thomson_PhD_F2013.pdf.

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This study examines phylogeography, population genetics, and introgression in birches (Betula spp.) of eastern North America with a specific focus on B. papyrifera Marsh., B. alleghaniensis Britt., and B. lenta L. Betula papyrifera (2n=56, 70, 84)occupies a wide variety of habitats across the transcontinental boreal zone and into northeastern temperate forests. Betula alleghaniensis (2n=84) is a mesophytic species occurring from southeastern Canada and New England to the southern Appalachians. Betula lenta (2n=28) is endemic to the Appalachian region of the United States, where it occurs primarily on moist, cool sites. Phylogeographic analyses based on chloroplast DNA (cpDNA) markers were used for inferring locations of glacial refugia and patterns of post-glacial migration. Nuclear microsatellite markers were used for investigating allelic richness, gene diversity, and genetic structure of populations of each species. The haplotype sharing among species was examined to elucidate patterns of cpDNA introgression, and nuclear microsatellite allele sharing was investigated to determine the incidence of nuclear genomic introgression. The cpDNA analyses revealed phylogeographic structuring of eastern and western populations of B. alleghaniensis and B. papyrifera suggesting postglacial colonization from separate refugia. The geographically structured patterns of regional cpDNA haplotype sharing between B. alleghaniensis and B. papyrifera suggest widespread introgression between species during the postglacial recolonization. In contrast, cpDNA markers were monomorphic in B. lenta and no haplotype sharing between B. lenta and other species were detected. Nuclear microsatellite data revealed low levels of population genetic substructure in each of the species with significant differentiation at larger spatial scales due to isolation by distance. The low level of population differentiation over relatively long distances probably reflects the long distance pollen and seed dispersal of these species. The analysis of nuclear microsatellite allele-sharing revealed that despite moderate to high proportions of shared alleles, each of the species was significantly genetically differentiated. No strong evidence of genetic introgression was found for B. alleghaniensis and B. lenta, or B. papyrifera and B. lenta. Admixture proportions were higher between B. alleghaniensis and B. papyrifera in the western Great Lakes, which is a previously-documented zone of hybridization based on the occurrence of morphological intermediates.

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Skillen, Elizabeth Lockard. « Diversity of parasitic Hymenoptera (Ichneumonidae : Campopleginae and Ichneumoninae) in Great Smoky Mountains National Park and eastern north American forests ». 2002. http://purl.galileo.usg.edu/uga%5Fetd/skillen%5Felizabeth%5Fl%5F200212%5Fphd.

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McCollister, Matthew Flanders. « Impacts of a 4-lane highway on the spatial ecology of American black bears and the effectiveness of wildlife underpasses in eastern North Carolina ». 2008. http://etd.utk.edu/2008/December2008MastersTheses/McCollisterMatthewFlanders.pdf.

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吳燕明. « Mineralogy and petrology of the rocks in the continental margin arc-oceanic crust contact zone in a backarc basin:as exemplified by the Laohushan raea, Eastern North Qilian Orogenic belt, NW China ». Thesis, 2001. http://ndltd.ncl.edu.tw/handle/32230691737276439714.

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Verdel, Charles Steven. « I. Cenozoic Geology of Iran : An Integrated Study of Extensional Tectonics and Related Vulcanism. II. Ediacaran Stratigraphy of the North American Cordillera : New Observations from Eastern California and Northern Utah ». Thesis, 2009. https://thesis.library.caltech.edu/3631/7/Verdel_thesis.pdf.

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I. The late Oligocene to Miocene collision of Arabia and Eurasia was preceded by ~175 My of subduction of Neotethyan oceanic crust. Associated magmatic activity includes late Triassic(?) to Jurassic plutons in the Sanandaj-Sirjan zone of southern Iran, limited Cretaceous magmatism in the Alborz Mountains of northern Iran, and widespread Eocene volcanism across central Iran. Metamorphic core complexes of Eocene age have recently been recognized in widely separated parts of Iran, suggesting that Tertiary volcanism was related to extension. Geochemical data indicate that Eocene volcanism was typical of continental arcs and was followed by less voluminous Oligocene basaltic volcanism of the type often associated with back-arc basins. This set of observations suggests that mid-Mesozoic plutons in southern Iran are the remnants of an original volcanic arc that was only weakly developed because of slow subduction rate. Magmatic activity largely ceased in southern and central Iran during the Cretaceous and shifted to the north, suggesting a period of flat slab subduction. Subsequent slab-rollback during the Eocene extended the overriding plate, forming metamorphic core complexes and inducing pressure-release melting of partially hydrated lithospheric mantle and upwelling of asthenosphere.

II. The Ediacaran Period spans from the base of cap carbonates overlying glacial deposits of the Marinoan “Snowball Earth” event to the Precambrian-Cambrian boundary, ~635 to 542 Ma. Sediments deposited during the rifting of southwest Laurentia, which are now exposed in a relatively narrow belt in the western US, are one of the best records on earth of the geological, geochemical, and geobiological events that occurred during this period. Evidence for one of the most significant of these, the final oxygenation of the oceans, is found within the upper Johnnie Formation in the southern Great Basin. C isotope data from thick, basinal facies of the Johnnie Fm. in the Panamint Range provide a more complete record of ocean chemistry associated with this event than previously determined from thinner, platformal facies. Strata in northern Utah of roughly the same age include a rift-related basalt, providing some of the youngest geologic evidence for the rifting of western Laurentia.

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(8850251), Ghaleb Alomaish. « “DOUBLE REFRACTION” : IMAGE PROJECTION AND PERCEPTION IN SAUDI-AMERICAN CONTEXTS : A COMPARATIVE STUDY ». Thesis, 2020.

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This dissertation aims to create a scholarly space where a seventy-five-year-old “special relationship” (1945-2020) between the Kingdom of Saudi Arabia and the United States is examined from an interdisciplinary comparativist perspective. I posit that a comparative study of Saudi and American fiction goes beyond the limitedness of global geopolitics and proves to uncover some new literary, sociocultural, and historical dimensions of this long history, while shedding some light on others. Saudi writers creatively challenge the inherently static and monolithic image of Saudi Arabia, its culture and people in the West. They also simultaneously unsettle the notion of homogeneity and enable us to gain new insight into self-perception within the local Saudi context by offering a wide scope of genuine engagements with distinctive themes ranging from spatiality, identity, ethnicity, and gender to slavery, religiosity and (post)modernity. On the other side, American authors still show some signs of ambivalence towards the depiction of the Saudi (Muslim/Arab) Other, but they nonetheless also demonstrate serious effort to emancipate their representations from the confining legacy of (neo)Orientalist discourse and oil politics by tackling the concepts of race, alterity, hegemony, radicalism, nomadism and (un)belonging.

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van, Kessel Irene. « All is One : Towawrd a Spirtual Whole Life Education based on an Inner Life Curriculum ». Thesis, 2012. http://hdl.handle.net/1807/32842.

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The intent of this thesis is to understand how we as educators and learners in our Western system of education can bridge and heal the fundamental principles of a constructed divide embedded in our consciousness that continues to be reproduced in our Western academy. The primary goal is to make visible this divide that is based on the intellectualization of Western education in the absence of spiritual aspirations, thus revealing the potential of spiritual transformation within the academy and our everyday lives. In my literature-based thesis research I explored, analyzed and discussed two bodies of literature: the historical intellectualization of Western education on the one hand, and, on the other, Eastern Philosophy with the emphasis on Higher Self Yoga, African Philosophy and North American Aboriginal Spirituality. I investigated these bodies of literature employing a research paradigm that has its foundation in a spiritual ontology and epistemology. I analyzed my findings using such methodologies as appreciative inquiry, content analysis and textual analysis, including anti-colonial and indigenous knowledges theoretical frameworks. I found that the synthesis and integration of the inner life wisdom revealed in the three philosophies is an integral component fundamental toward a whole life vision of education, an educative vision that has the potential to serve as a catalyst to open the gates for life-enhancing change in the academy and our everyday lives. Change implies becoming aware of our true origin, who we truly are, and what our intrinsic purpose is. Change implies becoming aware of humanity’s accelerated transition toward a higher level of spiritual planetary consciousness, a spiritual evolution as an inner quest of unity with nature, the larger human community, the universe, and the divine Source itself. Change implies whole life educational processes, inclusive of the unfoldment of inner life wisdom, the authority of the human spirit, and the sense of divinity, as useful bridging work in healing the divide in our aware consciousness and our educational institutions. Whole life change needs to be the responsibility of academic education, as well our self-responsibility of realizing ourselves as citizen of the world living within one-world consciousness. All is one.

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